Difference: ThematicTutorial3 (1 vs. 9)

Revision 92011-11-28 - EnriqueSolano

 
META TOPICPARENT name="ThematicTutorials"

Collinder 69: From SED fitting to Age estimation using VOSA


  • Step 1.- Go to http://svo.cab.inta-csic.es/theory/vosa.
  • Step 2.- To use VOSA you need to be registered. Click on "Register" and fill in the fields (email, name and passwd).
  • Step 3.- VOSA can be used to study stellar and extragalactic data. For this use case, click on "Stars and brown dwarfs".
  • Step 4.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase1.txt
  • Step 5.- Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type. Then, click "Upload".
  • Step 6.- In the new window, click on the corresponding radio button and then on "Select".
  • Step 7.- Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.
  • Step8.- We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.
  • Step9.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
  • Step11.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
    • After this, click on "Make the fit".
  • Step13.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model with the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step15.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step16.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step17.- A detailed description of how VOSA works can be found in the "Help" tag.

  • Use Case #2: Physical parameter determination of field, nearby stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase2.txt
  • Step 2.- Go to the "File" tag. Upload the file. Click on the corresponding radio button and then click "Select".
  • Step 3.-
    • Click on the "Objects" tag.
    • Retrieve the coordinates of our list of objects by cliking "Search for Obj. Coordinates".
    • Click on "Mark all: Sesame".
    • Click on "Save Obj. Coordinates".
  • Step 4.-
    • Move to the "Distances" tag.
    • Choose a search radius of 10 arcseconds.
    • Click on "Search for Obj. Distances".
    • Click on "Mark all: Hipparccos".
    • Click "Save Obj. Distances".
    • Skip the "Extinction" tag.
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS, Tycho-2 and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, only "Nextgen" is selected. Click on "Select model params".
  • Step8.- In this window, the range of physical parameters to be used in the fit can be refined. We will make the following assumption:
    • Nextgen: Teff: 2500-10000K; logg: 3.5-4.5
    • After this, click on "Make the fit".
  • Step9.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • HIP103: 6200K
    • HIP169: 4000K
    • HIP38: 5400K
    • HIP436: 4400K
    • HIP636: 8000K
  • Step10.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 (only Nextgen) and click on "Select model params". Then, click "Make the fit". Take the same range as in Step 8 (Teff: 2500-10000K; logg: 3.5-4.5). A summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step11.- In order to see how our objects are distributed in a HR diagram, we will make use of the "HR Diag." tab. Four of them lie outside the area covered by the isochrones/evol. tracks. You can "clean" the plot by clicking on "Unmark all" (top left in "Models" table). Change the limits in the X,Y-axis (X: 3500-8500K; Y: -1.5,1.5). Click on "Plot" again. Compare what you get with the image given below. hr.jpg


  • Use Case #3: Physical parameter determination of highly reddened stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase3
  • Step 2.- Go to the "File" tag. Upload the file. Click on the corresponding radio button and then click "Select".
  • Step 3.-
    • Click on the "Objects" tag.
    • Retrieve the coordinates of HE1136-1641 by clicking "Search for Obj. Coordinates".
    • Tick on "Sesame" for HE1136-1641.
    • Click on "Save Obj. Coordinates".
  • Step 4.-
    • Move to the "Extinction" tag (skip the "Distances" tag).
    • Click on "Search for Extinction properties".
Changed:
<
<
    • Add a defaul Rv value of 3.1. Click on "Add".
>
>
    • Add a defaul Rv value of 3.1. for obj13 and obj15
 
    • Click on Mark All: "User", "Larson", "Savage", "Morales" (click four times).
    • Click on "Save Ext. properties".
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select 2MASS, Tycho-2, CMC-14, Stromgren and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before fitting a model. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, we select "Nextgen", "Kurucz" and "Tlusty". Click on "Select model params". Do not change the parameter range. Then click on "Make the fit".
  • Step8.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
Changed:
<
<
    • HE1136-1641: 45000K (Tlusty)
>
>
    • HE1136-1641: 37500K (Tlusty)
 
    • obj13: 8800K (Nextgen)
    • obj15: 21000K (Kurucz)
    • obj25: 9000K (Nextgen)
Changed:
<
<
    • obj26: 20000K (Kurucz)
>
>
    • obj26: 21000K (Tlusty)
 
  • Step9.-
    • Go back to the "Files" tag.
    • Upload the file vosa_usecase3b
    • Tick the corresponding radio button.
    • Click "Select"
  • Step10.- Repeat Step 3 to gather the coordinates of HE1136-1641.
  • Step11.- Skip the "Distances" and "Extinction" tags .
  • Step12.- Repeat Steps 5-8. You should obtain the following temperatures:
Changed:
<
<
    • HE1136-1641: 30000K (Tlusty)
    • obj13: 5000K (Nextgen)
    • obj15: 12750K (Kurucz)
    • obj25: 5500K (Nextgen)
    • obj26: 9200K (Kurucz)
>
>
    • HE1136-1641: 35000K (Tlusty)
    • obj13: 5000K (Kurucz)
    • obj15: 12500K (Kurucz)
    • obj25: 5500K (Kurucz)
    • obj26: 9200K (Nextgen)
 
  • Step13.- Click on "Show graphs" to have a look at the graphics. Apparently the fitting is excellent in all cases. What is causing the large differences in Teff is we compare these values with those calculated in Step8? The answer is the extinction (we are now assuming no extinction) which has a strong impact on the SED shape. In the figure given below, red circles represent the observed SED of a star with E(B-V)=0.76. Blue squares represent the SED of the same star after the reddening correction. Forget about the green triangles.
no_ext.png

back to main twiki page for the school

META FILEATTACHMENT attachment="vosa_usecase1.txt" attr="" comment="VOSA. Use Case #1. Data" date="1300367449" name="vosa_usecase1.txt" path="vosa_usecase1.txt" size="3367" user="EnriqueSolano" version="1"
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Revision 82011-03-18 - CarolineBot

 
META TOPICPARENT name="ThematicTutorials"
Added:
>
>

Collinder 69: From SED fitting to Age estimation using VOSA


 
  • Step 1.- Go to http://svo.cab.inta-csic.es/theory/vosa.
  • Step 2.- To use VOSA you need to be registered. Click on "Register" and fill in the fields (email, name and passwd).
  • Step 3.- VOSA can be used to study stellar and extragalactic data. For this use case, click on "Stars and brown dwarfs".
  • Step 4.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase1.txt
  • Step 5.- Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type. Then, click "Upload".
  • Step 6.- In the new window, click on the corresponding radio button and then on "Select".
  • Step 7.- Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.
  • Step8.- We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.
  • Step9.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
  • Step11.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
    • After this, click on "Make the fit".
  • Step13.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model with the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step15.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step16.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step17.- A detailed description of how VOSA works can be found in the "Help" tag.

  • Use Case #2: Physical parameter determination of field, nearby stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase2.txt
  • Step 2.- Go to the "File" tag. Upload the file. Click on the corresponding radio button and then click "Select".
  • Step 3.-
    • Click on the "Objects" tag.
    • Retrieve the coordinates of our list of objects by cliking "Search for Obj. Coordinates".
    • Click on "Mark all: Sesame".
    • Click on "Save Obj. Coordinates".
  • Step 4.-
    • Move to the "Distances" tag.
    • Choose a search radius of 10 arcseconds.
    • Click on "Search for Obj. Distances".
    • Click on "Mark all: Hipparccos".
    • Click "Save Obj. Distances".
    • Skip the "Extinction" tag.
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS, Tycho-2 and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, only "Nextgen" is selected. Click on "Select model params".
  • Step8.- In this window, the range of physical parameters to be used in the fit can be refined. We will make the following assumption:
    • Nextgen: Teff: 2500-10000K; logg: 3.5-4.5
    • After this, click on "Make the fit".
  • Step9.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • HIP103: 6200K
    • HIP169: 4000K
    • HIP38: 5400K
    • HIP436: 4400K
    • HIP636: 8000K
  • Step10.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 (only Nextgen) and click on "Select model params". Then, click "Make the fit". Take the same range as in Step 8 (Teff: 2500-10000K; logg: 3.5-4.5). A summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step11.- In order to see how our objects are distributed in a HR diagram, we will make use of the "HR Diag." tab. Four of them lie outside the area covered by the isochrones/evol. tracks. You can "clean" the plot by clicking on "Unmark all" (top left in "Models" table). Change the limits in the X,Y-axis (X: 3500-8500K; Y: -1.5,1.5). Click on "Plot" again. Compare what you get with the image given below. hr.jpg


  • Use Case #3: Physical parameter determination of highly reddened stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase3
  • Step 2.- Go to the "File" tag. Upload the file. Click on the corresponding radio button and then click "Select".
  • Step 3.-
    • Click on the "Objects" tag.
    • Retrieve the coordinates of HE1136-1641 by clicking "Search for Obj. Coordinates".
    • Tick on "Sesame" for HE1136-1641.
    • Click on "Save Obj. Coordinates".
  • Step 4.-
    • Move to the "Extinction" tag (skip the "Distances" tag).
    • Click on "Search for Extinction properties".
    • Add a defaul Rv value of 3.1. Click on "Add".
    • Click on Mark All: "User", "Larson", "Savage", "Morales" (click four times).
    • Click on "Save Ext. properties".
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select 2MASS, Tycho-2, CMC-14, Stromgren and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before fitting a model. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, we select "Nextgen", "Kurucz" and "Tlusty". Click on "Select model params". Do not change the parameter range. Then click on "Make the fit".
  • Step8.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • HE1136-1641: 45000K (Tlusty)
    • obj13: 8800K (Nextgen)
    • obj15: 21000K (Kurucz)
    • obj25: 9000K (Nextgen)
    • obj26: 20000K (Kurucz)
  • Step9.-
    • Go back to the "Files" tag.
    • Upload the file vosa_usecase3b
    • Tick the corresponding radio button.
    • Click "Select"
  • Step10.- Repeat Step 3 to gather the coordinates of HE1136-1641.
  • Step11.- Skip the "Distances" and "Extinction" tags .
  • Step12.- Repeat Steps 5-8. You should obtain the following temperatures:
    • HE1136-1641: 30000K (Tlusty)
    • obj13: 5000K (Nextgen)
    • obj15: 12750K (Kurucz)
    • obj25: 5500K (Nextgen)
    • obj26: 9200K (Kurucz)
  • Step13.- Click on "Show graphs" to have a look at the graphics. Apparently the fitting is excellent in all cases. What is causing the large differences in Teff is we compare these values with those calculated in Step8? The answer is the extinction (we are now assuming no extinction) which has a strong impact on the SED shape. In the figure given below, red circles represent the observed SED of a star with E(B-V)=0.76. Blue squares represent the SED of the same star after the reddening correction. Forget about the green triangles.
no_ext.png
Added:
>
>
back to main twiki page for the school
 
META FILEATTACHMENT attachment="vosa_usecase1.txt" attr="" comment="VOSA. Use Case #1. Data" date="1300367449" name="vosa_usecase1.txt" path="vosa_usecase1.txt" size="3367" user="EnriqueSolano" version="1"
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Revision 72011-03-18 - EnriqueSolano

 
META TOPICPARENT name="ThematicTutorials"
Changed:
<
<
  • Title: From SED fitting to Age estimation: The case of Collinder 69
>
>
  • Title: From SED fitting to Age estimation using VOSA
 
Deleted:
<
<
  • Data to be used: Here we will use a subset of the objects studied in Bayo, A. et al. ( 2008, A&A 492..277B). The list of objects in "VOSA format" is given below.
 
  • Use Case #1: Collinder 69 candidate members. Determination of physical parameters.
Changed:
<
<
>
>
 
  • Step 1.- Go to http://svo.cab.inta-csic.es/theory/vosa.
  • Step 2.- To use VOSA you need to be registered. Click on "Register" and fill in the fields (email, name and passwd).
  • Step 3.- VOSA can be used to study stellar and extragalactic data. For this use case, click on "Stars and brown dwarfs".
  • Step 4.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase1.txt
Changed:
<
<
  • Step 5.- Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type.
>
>
  • Step 5.- Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type. Then, click "Upload".
 
  • Step 6.- In the new window, click on the corresponding radio button and then on "Select".
  • Step 7.- Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.
  • Step8.- We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.
  • Step9.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
  • Step11.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
    • After this, click on "Make the fit".
  • Step13.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
Changed:
<
<
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
>
>
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model with the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
 
  • Step15.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step16.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step17.- A detailed description of how VOSA works can be found in the "Help" tag.

  • Use Case #2: Physical parameter determination of field, nearby stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase2.txt
  • Step 2.- Go to the "File" tag. Upload the file. Click on the corresponding radio button and then click "Select".
Changed:
<
<
  • Step 3.- Click on the "Objects" tag. Retrieve the coordinates of our list of objects by cliking "Search for Obj. Coordinates". Click on "Mark all: Sesame". Click on "Save Obj. Coordinates".
  • Step 4.- Move to the "Distances" tag. Click on "Search for Obj. Distances". Choose a search radius of 10 arcseconds. Then, click on "Mark all: Hipparccos". Click "Save Obj. Distances". Skip the "Extinction" tag.
>
>
  • Step 3.-
    • Click on the "Objects" tag.
Added:
>
>
    • Retrieve the coordinates of our list of objects by cliking "Search for Obj. Coordinates".
    • Click on "Mark all: Sesame".
    • Click on "Save Obj. Coordinates".
  • Step 4.-
    • Move to the "Distances" tag.
    • Choose a search radius of 10 arcseconds.
    • Click on "Search for Obj. Distances".
    • Click on "Mark all: Hipparccos".
    • Click "Save Obj. Distances".
    • Skip the "Extinction" tag.
 
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS, Tycho-2 and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, only "Nextgen" is selected. Click on "Select model params".
  • Step8.- In this window, the range of physical parameters to be used in the fit can be refined. We will make the following assumption:
    • Nextgen: Teff: 2500-10000K; logg: 3.5-4.5
    • After this, click on "Make the fit".
  • Step9.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • HIP103: 6200K
    • HIP169: 4000K
    • HIP38: 5400K
    • HIP436: 4400K
    • HIP636: 8000K
  • Step10.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 (only Nextgen) and click on "Select model params". Then, click "Make the fit". Take the same range as in Step 8 (Teff: 2500-10000K; logg: 3.5-4.5). A summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
Changed:
<
<
  • Step11.- In order to see how our objects are distributed in a HR diagram, we will make use of the "HR Diag." tab. Four of them lie outside the area covered by the isochrones/evol. tracks. You can "clean" the plot by clicking on "Unmark all" (top left) and click on "Plot" again. Compare what you get with the image given below. hr.jpg
>
>
  • Step11.- In order to see how our objects are distributed in a HR diagram, we will make use of the "HR Diag." tab. Four of them lie outside the area covered by the isochrones/evol. tracks. You can "clean" the plot by clicking on "Unmark all" (top left in "Models" table). Change the limits in the X,Y-axis (X: 3500-8500K; Y: -1.5,1.5). Click on "Plot" again. Compare what you get with the image given below. hr.jpg
 


  • Use Case #3: Physical parameter determination of highly reddened stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase3
  • Step 2.- Go to the "File" tag. Upload the file. Click on the corresponding radio button and then click "Select".
  • Step 3.-
    • Click on the "Objects" tag.
    • Retrieve the coordinates of HE1136-1641 by clicking "Search for Obj. Coordinates".
    • Tick on "Sesame" for HE1136-1641.
    • Click on "Save Obj. Coordinates".
  • Step 4.-
    • Move to the "Extinction" tag (skip the "Distances" tag).
    • Click on "Search for Extinction properties".
    • Add a defaul Rv value of 3.1. Click on "Add".
Changed:
<
<
    • Tick on "user data" for HE1136-1641 and on VO data for the rest of the objects.
>
>
    • Click on Mark All: "User", "Larson", "Savage", "Morales" (click four times).
 
    • Click on "Save Ext. properties".
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select 2MASS, Tycho-2, CMC-14, Stromgren and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before fitting a model. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, we select "Nextgen", "Kurucz" and "Tlusty". Click on "Select model params". Do not change the parameter range. Then click on "Make the fit".
  • Step8.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • HE1136-1641: 45000K (Tlusty)
    • obj13: 8800K (Nextgen)
    • obj15: 21000K (Kurucz)
    • obj25: 9000K (Nextgen)
    • obj26: 20000K (Kurucz)
  • Step9.-
    • Go back to the "Files" tag.
    • Upload the file vosa_usecase3b
    • Tick the corresponding radio button.
    • Click "Select"
  • Step10.- Repeat Step 3 to gather the coordinates of HE1136-1641.
  • Step11.- Skip the "Distances" and "Extinction" tags .
  • Step12.- Repeat Steps 5-8. You should obtain the following temperatures:
    • HE1136-1641: 30000K (Tlusty)
    • obj13: 5000K (Nextgen)
    • obj15: 12750K (Kurucz)
    • obj25: 5500K (Nextgen)
    • obj26: 9200K (Kurucz)
Changed:
<
<
  • Step13.- Click on "Show graphs" to have a look at the graphics. Apparently the fitting is excellent in all cases. What is causing the large differences in Teff is we compare these values with those calculated in Step8? The answer is the extinction (we are now assuming no extinction) which has a strong impact on the SED shape. In the figure given below, red circles represent the observed SED of a star with E(B-V)=0.76. Blue squares represent the SED of the same star after the reddening correction.
>
>
  • Step13.- Click on "Show graphs" to have a look at the graphics. Apparently the fitting is excellent in all cases. What is causing the large differences in Teff is we compare these values with those calculated in Step8? The answer is the extinction (we are now assuming no extinction) which has a strong impact on the SED shape. In the figure given below, red circles represent the observed SED of a star with E(B-V)=0.76. Blue squares represent the SED of the same star after the reddening correction. Forget about the green triangles.
 no_ext.png

META FILEATTACHMENT attachment="vosa_usecase1.txt" attr="" comment="VOSA. Use Case #1. Data" date="1300367449" name="vosa_usecase1.txt" path="vosa_usecase1.txt" size="3367" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase2.txt" attr="" comment="VOSA. Use Case #2. Data" date="1300372813" name="vosa_usecase2.txt" path="vosa_usecase2.txt" size="180" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="hr.jpg" attr="" comment="HR" date="1300398026" name="hr.jpg" path="hr.jpg" size="43638" user="EnriqueSolano" version="2"
META FILEATTACHMENT attachment="vosa_usecase3.txt.txt" attr="" comment="VOSA. Use Case #3. Data" date="1300400478" name="vosa_usecase3.txt.txt" path="vosa_usecase3.txt.txt" size="251" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase3.txt" attr="" comment="" date="1300400697" name="vosa_usecase3.txt" path="vosa_usecase3.txt" size="251" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase3" attr="" comment="" date="1300401299" name="vosa_usecase3" path="vosa_usecase3" size="210" user="EnriqueSolano" version="3"
META FILEATTACHMENT attachment="vosa_usecase3b" attr="" comment="" date="1300402566" name="vosa_usecase3b" path="vosa_usecase3b" size="209" user="EnriqueSolano" version="2"
META FILEATTACHMENT attachment="no_ext.png" attr="" comment="Effect of extinction on SED" date="1300440092" name="no_ext.png" path="no_ext.png" size="6580" user="EnriqueSolano" version="1"

Revision 62011-03-18 - EnriqueSolano

 
META TOPICPARENT name="ThematicTutorials"
  • Title: From SED fitting to Age estimation: The case of Collinder 69
  • Tools to be used: VOSA http://svo.cab.inta-csic.es/theory/vosa
  • Data to be used: Here we will use a subset of the objects studied in Bayo, A. et al. ( 2008, A&A 492..277B). The list of objects in "VOSA format" is given below.
  • Use Case #1: Collinder 69 candidate members. Determination of physical parameters.
  • Step 1.- Go to http://svo.cab.inta-csic.es/theory/vosa.
  • Step 2.- To use VOSA you need to be registered. Click on "Register" and fill in the fields (email, name and passwd).
  • Step 3.- VOSA can be used to study stellar and extragalactic data. For this use case, click on "Stars and brown dwarfs".
  • Step 4.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase1.txt
  • Step 5.- Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type.
Changed:
<
<
  • Step 6.- In the new window, click on the radio button and then on "Select".
>
>
  • Step 6.- In the new window, click on the corresponding radio button and then on "Select".
 
  • Step 7.- Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.
  • Step8.- We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.
  • Step9.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
Changed:
<
<
  • Step11.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
>
>
  • Step11.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
 
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
    • After this, click on "Make the fit".
Changed:
<
<
  • Step13.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
>
>
  • Step13.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
 
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step15.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step16.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step17.- A detailed description of how VOSA works can be found in the "Help" tag.

  • Use Case #2: Physical parameter determination of field, nearby stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase2.txt
Changed:
<
<
  • Step 2.- Go to the "File" tag. Upload the file. Click on the radio button and then click "Select".
>
>
  • Step 2.- Go to the "File" tag. Upload the file. Click on the corresponding radio button and then click "Select".
 
  • Step 3.- Click on the "Objects" tag. Retrieve the coordinates of our list of objects by cliking "Search for Obj. Coordinates". Click on "Mark all: Sesame". Click on "Save Obj. Coordinates".
  • Step 4.- Move to the "Distances" tag. Click on "Search for Obj. Distances". Choose a search radius of 10 arcseconds. Then, click on "Mark all: Hipparccos". Click "Save Obj. Distances". Skip the "Extinction" tag.
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS, Tycho-2 and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
Changed:
<
<
  • Step7.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, only "Kurucz" is selected. Click on "Select model params".
>
>
  • Step7.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, only "Nextgen" is selected. Click on "Select model params".
 
  • Step8.- In this window, the range of physical parameters to be used in the fit can be refined. We will make the following assumption:
    • Nextgen: Teff: 2500-10000K; logg: 3.5-4.5
    • After this, click on "Make the fit".
Changed:
<
<
  • Step9.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
>
>
  • Step9.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
 
    • HIP103: 6200K
Changed:
<
<
    • HIP169: 3900K
>
>
    • HIP169: 4000K
 
    • HIP38: 5400K
    • HIP436: 4400K
    • HIP636: 8000K
Changed:
<
<
  • Step10.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 (only Nextgen) and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
>
>
  • Step10.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 (only Nextgen) and click on "Select model params". Then, click "Make the fit". Take the same range as in Step 8 (Teff: 2500-10000K; logg: 3.5-4.5). A summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
 
  • Step11.- In order to see how our objects are distributed in a HR diagram, we will make use of the "HR Diag." tab. Four of them lie outside the area covered by the isochrones/evol. tracks. You can "clean" the plot by clicking on "Unmark all" (top left) and click on "Plot" again. Compare what you get with the image given below. hr.jpg


  • Use Case #3: Physical parameter determination of highly reddened stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase3
Changed:
<
<
  • Step 2.- Go to the "File" tag. Upload the file. Click on the radio button and then click "Select".
  • Step 3.- Click on the "Objects" tag. Retrieve the coordinates of HE1136-1641 by cliking "Search for Obj. Coordinates". Tick on "Sesame" for HE1136-1641. Click on "Save Obj. Coordinates".
  • Step 4.- Move to the "Extinction" tag (skip the "Distances" tag). Click on "Search for Extinction properties". Add a defaul Rv value of 3.1. Tick on "user data" for HE1136-1641 and on VO data for the rest of the objects. Then click on "Mark all: User, Larson, Savage, Morales" (click four times one for each catalogue). Click on "Save Ext. properties".
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS, Tycho-2, CMC-14, Stromgren and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select "Nextgen", "Kurucz" and "Tlusty". Click on "Select model params". Do not change the parameter range. Then click on "Make the fit".
  • Step9.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • HE1136-1641: 45000K
    • obj13: 8800K
    • obj15: 21000K
    • obj25: 9000K
    • obj26: 20000K
  • Step10.- Go to "File" tag. Upload the file vosa_usecase3b
  • Repeat the Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 (only Nextgen) and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step11.- In order to see how our objects are distributed in a HR diagram, we will make use of the "HR Diag." tab. Four of them lie outside the area covered by the isochrones/evol. tracks. You can "clean" the plot by clicking on "Unmark all" (top left) and click on "Plot" again. Compare what you get with the image given below.
back to main twiki page for the school
>
>
  • Step 2.- Go to the "File" tag. Upload the file. Click on the corresponding radio button and then click "Select".
  • Step 3.-
    • Click on the "Objects" tag.
    • Retrieve the coordinates of HE1136-1641 by clicking "Search for Obj. Coordinates".
    • Tick on "Sesame" for HE1136-1641.
    • Click on "Save Obj. Coordinates".
  • Step 4.-
    • Move to the "Extinction" tag (skip the "Distances" tag).
    • Click on "Search for Extinction properties".
    • Add a defaul Rv value of 3.1. Click on "Add".
    • Tick on "user data" for HE1136-1641 and on VO data for the rest of the objects.
    • Click on "Save Ext. properties".
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select 2MASS, Tycho-2, CMC-14, Stromgren and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before fitting a model. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), different grids of theoretical models are displayed. They cover different ranges of physical parameters. For this case, we select "Nextgen", "Kurucz" and "Tlusty". Click on "Select model params". Do not change the parameter range. Then click on "Make the fit".
  • Step8.- We can now see a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
Added:
>
>
    • HE1136-1641: 45000K (Tlusty)
    • obj13: 8800K (Nextgen)
    • obj15: 21000K (Kurucz)
    • obj25: 9000K (Nextgen)
    • obj26: 20000K (Kurucz)
  • Step9.-
    • Go back to the "Files" tag.
    • Upload the file vosa_usecase3b
    • Tick the corresponding radio button.
    • Click "Select"
  • Step10.- Repeat Step 3 to gather the coordinates of HE1136-1641.
  • Step11.- Skip the "Distances" and "Extinction" tags .
  • Step12.- Repeat Steps 5-8. You should obtain the following temperatures:
    • HE1136-1641: 30000K (Tlusty)
    • obj13: 5000K (Nextgen)
    • obj15: 12750K (Kurucz)
    • obj25: 5500K (Nextgen)
    • obj26: 9200K (Kurucz)
  • Step13.- Click on "Show graphs" to have a look at the graphics. Apparently the fitting is excellent in all cases. What is causing the large differences in Teff is we compare these values with those calculated in Step8? The answer is the extinction (we are now assuming no extinction) which has a strong impact on the SED shape. In the figure given below, red circles represent the observed SED of a star with E(B-V)=0.76. Blue squares represent the SED of the same star after the reddening correction.
no_ext.png
 
Deleted:
<
<
-- CarolineBot - 2011-02-07

-- EnriqueSolano - 2011-03-17

 
META FILEATTACHMENT attachment="vosa_usecase1.txt" attr="" comment="VOSA. Use Case #1. Data" date="1300367449" name="vosa_usecase1.txt" path="vosa_usecase1.txt" size="3367" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase2.txt" attr="" comment="VOSA. Use Case #2. Data" date="1300372813" name="vosa_usecase2.txt" path="vosa_usecase2.txt" size="180" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="hr.jpg" attr="" comment="HR" date="1300398026" name="hr.jpg" path="hr.jpg" size="43638" user="EnriqueSolano" version="2"
META FILEATTACHMENT attachment="vosa_usecase3.txt.txt" attr="" comment="VOSA. Use Case #3. Data" date="1300400478" name="vosa_usecase3.txt.txt" path="vosa_usecase3.txt.txt" size="251" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase3.txt" attr="" comment="" date="1300400697" name="vosa_usecase3.txt" path="vosa_usecase3.txt" size="251" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase3" attr="" comment="" date="1300401299" name="vosa_usecase3" path="vosa_usecase3" size="210" user="EnriqueSolano" version="3"
META FILEATTACHMENT attachment="vosa_usecase3b" attr="" comment="" date="1300402566" name="vosa_usecase3b" path="vosa_usecase3b" size="209" user="EnriqueSolano" version="2"
Added:
>
>
META FILEATTACHMENT attachment="no_ext.png" attr="" comment="Effect of extinction on SED" date="1300440092" name="no_ext.png" path="no_ext.png" size="6580" user="EnriqueSolano" version="1"
 

Revision 52011-03-17 - EnriqueSolano

 
META TOPICPARENT name="ThematicTutorials"
Changed:
<
<
  • Title: From SED fitting to Age estimation: The case of Collinder 69
>
>
  • Title: From SED fitting to Age estimation: The case of Collinder 69
 
  • Step 1.- Go to http://svo.cab.inta-csic.es/theory/vosa.
  • Step 2.- To use VOSA you need to be registered. Click on "Register" and fill in the fields (email, name and passwd).
  • Step 3.- VOSA can be used to study stellar and extragalactic data. For this use case, click on "Stars and brown dwarfs".
  • Step 4.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase1.txt
  • Step 5.- Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type.
  • Step 6.- In the new window, click on the radio button and then on "Select".
  • Step 7.- Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.
  • Step8.- We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.
  • Step9.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
  • Step11.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
    • After this, click on "Make the fit".
  • Step13.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
Changed:
<
<
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters.
  • Step15.- For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step16.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step17.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
>
>
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step15.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step16.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step17.- A detailed description of how VOSA works can be found in the "Help" tag.
Deleted:
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<
  • Step18.- A detailed description of how VOSA works can be found in the "Help" tag.
 

  • Use Case #2: Physical parameter determination of field, nearby stars.
Changed:
<
<
>
>
 
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase2.txt
  • Step 2.- Go to the "File" tag. Upload the file. Click on the radio button and then click "Select".
  • Step 3.- Click on the "Objects" tag. Retrieve the coordinates of our list of objects by cliking "Search for Obj. Coordinates". Click on "Mark all: Sesame". Click on "Save Obj. Coordinates".
  • Step 4.- Move to the "Distances" tag. Click on "Search for Obj. Distances". Choose a search radius of 10 arcseconds. Then, click on "Mark all: Hipparccos". Click "Save Obj. Distances". Skip the "Extinction" tag.
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS, Tycho-2 and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
Changed:
<
<
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, on "Nextgen" is selected. Click on "Select model params".
>
>
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, only "Kurucz" is selected. Click on "Select model params".
 
  • Step8.- In this window, the range of physical parameters to be used in the fit can be refined. We will make the following assumption:
    • Nextgen: Teff: 2500-10000K; logg: 3.5-4.5
    • After this, click on "Make the fit".
  • Step9.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
Changed:
<
<
    • HIP103: 6200K
    • HIP169: 3900K
>
>
    • HIP103: 6200K
    • HIP169: 3900K
 
    • HIP38: 5400K
Changed:
<
<
    • HIP436: 4400K
    • HIP636: 8000K
  • Step10.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters.
  • Step15.- For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
>
>
    • HIP436: 4400K
    • HIP636: 8000K
  • Step10.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 (only Nextgen) and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step11.- In order to see how our objects are distributed in a HR diagram, we will make use of the "HR Diag." tab. Four of them lie outside the area covered by the isochrones/evol. tracks. You can "clean" the plot by clicking on "Unmark all" (top left) and click on "Plot" again. Compare what you get with the image given below. hr.jpg
Deleted:
<
<
  • Step16.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step17.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step18.- A detailed description of how VOSA works can be found in the "Help" tag.
 
Added:
>
>
 
Added:
>
>
  • Use Case #3: Physical parameter determination of highly reddened stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase3
  • Step 2.- Go to the "File" tag. Upload the file. Click on the radio button and then click "Select".
  • Step 3.- Click on the "Objects" tag. Retrieve the coordinates of HE1136-1641 by cliking "Search for Obj. Coordinates". Tick on "Sesame" for HE1136-1641. Click on "Save Obj. Coordinates".
  • Step 4.- Move to the "Extinction" tag (skip the "Distances" tag). Click on "Search for Extinction properties". Add a defaul Rv value of 3.1. Tick on "user data" for HE1136-1641 and on VO data for the rest of the objects. Then click on "Mark all: User, Larson, Savage, Morales" (click four times one for each catalogue). Click on "Save Ext. properties".
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS, Tycho-2, CMC-14, Stromgren and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select "Nextgen", "Kurucz" and "Tlusty". Click on "Select model params". Do not change the parameter range. Then click on "Make the fit".
  • Step9.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • HE1136-1641: 45000K
    • obj13: 8800K
    • obj15: 21000K
    • obj25: 9000K
    • obj26: 20000K
  • Step10.- Go to "File" tag. Upload the file vosa_usecase3b
  • Repeat the Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 (only Nextgen) and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters. For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step11.- In order to see how our objects are distributed in a HR diagram, we will make use of the "HR Diag." tab. Four of them lie outside the area covered by the isochrones/evol. tracks. You can "clean" the plot by clicking on "Unmark all" (top left) and click on "Plot" again. Compare what you get with the image given below.
 back to main twiki page for the school

-- CarolineBot - 2011-02-07

-- EnriqueSolano - 2011-03-17

Added:
>
>

 
META FILEATTACHMENT attachment="vosa_usecase1.txt" attr="" comment="VOSA. Use Case #1. Data" date="1300367449" name="vosa_usecase1.txt" path="vosa_usecase1.txt" size="3367" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase2.txt" attr="" comment="VOSA. Use Case #2. Data" date="1300372813" name="vosa_usecase2.txt" path="vosa_usecase2.txt" size="180" user="EnriqueSolano" version="1"
Added:
>
>
META FILEATTACHMENT attachment="hr.jpg" attr="" comment="HR" date="1300398026" name="hr.jpg" path="hr.jpg" size="43638" user="EnriqueSolano" version="2"
META FILEATTACHMENT attachment="vosa_usecase3.txt.txt" attr="" comment="VOSA. Use Case #3. Data" date="1300400478" name="vosa_usecase3.txt.txt" path="vosa_usecase3.txt.txt" size="251" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase3.txt" attr="" comment="" date="1300400697" name="vosa_usecase3.txt" path="vosa_usecase3.txt" size="251" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase3" attr="" comment="" date="1300401299" name="vosa_usecase3" path="vosa_usecase3" size="210" user="EnriqueSolano" version="3"
META FILEATTACHMENT attachment="vosa_usecase3b" attr="" comment="" date="1300402566" name="vosa_usecase3b" path="vosa_usecase3b" size="209" user="EnriqueSolano" version="2"
 

Revision 42011-03-17 - EnriqueSolano

 
META TOPICPARENT name="ThematicTutorials"
  • Title: From SED fitting to Age estimation: The case of Collinder 69
  • Tools to be used: VOSA http://svo.cab.inta-csic.es/theory/vosa
  • Data to be used: Here we will use a subset of the objects studied in Bayo, A. et al. ( 2008, A&A 492..277B). The list of objects in "VOSA format" is given below.
  • Use Case #1: Collinder 69 candidate members. Determination of physical parameters.
  • Step 1.- Go to http://svo.cab.inta-csic.es/theory/vosa.
  • Step 2.- To use VOSA you need to be registered. Click on "Register" and fill in the fields (email, name and passwd).
  • Step 3.- VOSA can be used to study stellar and extragalactic data. For this use case, click on "Stars and brown dwarfs".
  • Step 4.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase1.txt
  • Step 5.- Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type.
  • Step 6.- In the new window, click on the radio button and then on "Select".
  • Step 7.- Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.
  • Step8.- We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.
  • Step9.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
  • Step11.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
    • After this, click on "Make the fit".
  • Step13.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters.
  • Step15.- For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step16.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step17.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step18.- A detailed description of how VOSA works can be found in the "Help" tag.

  • Use Case #2: Physical parameter determination of field, nearby stars.
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase2.txt
  • Step 2.- Go to the "File" tag. Upload the file. Click on the radio button and then click "Select".
  • Step 3.- Click on the "Objects" tag. Retrieve the coordinates of our list of objects by cliking "Search for Obj. Coordinates". Click on "Mark all: Sesame". Click on "Save Obj. Coordinates".
  • Step 4.- Move to the "Distances" tag. Click on "Search for Obj. Distances". Choose a search radius of 10 arcseconds. Then, click on "Mark all: Hipparccos". Click "Save Obj. Distances". Skip the "Extinction" tag.
Changed:
<
<
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
  • Step11.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
>
>
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS, Tycho-2 and GALEX. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step6.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Do not make any modification to what VOSA shows in this page.
  • Step7.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, on "Nextgen" is selected. Click on "Select model params".
  • Step8.- In this window, the range of physical parameters to be used in the fit can be refined. We will make the following assumption:
    • Nextgen: Teff: 2500-10000K; logg: 3.5-4.5
Deleted:
<
<
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
 
    • After this, click on "Make the fit".
Changed:
<
<
  • Step13.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters.
>
>
  • Step9.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • HIP103: 6200K
    • HIP169: 3900K
    • HIP38: 5400K
    • HIP436: 4400K
    • HIP636: 8000K
  • Step10.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step7 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters.
 
  • Step15.- For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step16.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step17.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step18.- A detailed description of how VOSA works can be found in the "Help" tag.

back to main twiki page for the school

-- CarolineBot - 2011-02-07

-- EnriqueSolano - 2011-03-17

META FILEATTACHMENT attachment="vosa_usecase1.txt" attr="" comment="VOSA. Use Case #1. Data" date="1300367449" name="vosa_usecase1.txt" path="vosa_usecase1.txt" size="3367" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase2.txt" attr="" comment="VOSA. Use Case #2. Data" date="1300372813" name="vosa_usecase2.txt" path="vosa_usecase2.txt" size="180" user="EnriqueSolano" version="1"

Revision 32011-03-17 - EnriqueSolano

 
META TOPICPARENT name="ThematicTutorials"
  • Title: From SED fitting to Age estimation: The case of Collinder 69
Changed:
<
<
>
>
 
  • Data to be used: Here we will use a subset of the objects studied in Bayo, A. et al. ( 2008, A&A 492..277B). The list of objects in "VOSA format" is given below.
Changed:
<
<
  • Workflow: The step-by-step use case can be found here
  • Use Case #1: Collinder 69 candidate members. Determination of physical parameters.
>
>
  • Use Case #1: Collinder 69 candidate members. Determination of physical parameters.
 
Changed:
<
<
>
>
  • Step 1.- Go to http://svo.cab.inta-csic.es/theory/vosa.
  • Step 2.- To use VOSA you need to be registered. Click on "Register" and fill in the fields (email, name and passwd).
  • Step 3.- VOSA can be used to study stellar and extragalactic data. For this use case, click on "Stars and brown dwarfs".
  • Step 4.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase1.txt
  • Step 5.- Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type.
  • Step 6.- In the new window, click on the radio button and then on "Select".
  • Step 7.- Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.
Added:
>
>
  • Step8.- We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.
  • Step9.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
  • Step11.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
    • After this, click on "Make the fit".
  • Step13.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters.
  • Step15.- For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step16.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step17.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step18.- A detailed description of how VOSA works can be found in the "Help" tag.
 
Deleted:
<
<
** 

 
Changed:
<
<
** **
>
>
  • Use Case #2: Physical parameter determination of field, nearby stars.
Added:
>
>
  • Step 1.- Cut and paste in a file the list of objects in "VOSA format" included in vosa_usecase2.txt
  • Step 2.- Go to the "File" tag. Upload the file. Click on the radio button and then click "Select".
  • Step 3.- Click on the "Objects" tag. Retrieve the coordinates of our list of objects by cliking "Search for Obj. Coordinates". Click on "Mark all: Sesame". Click on "Save Obj. Coordinates".
  • Step 4.- Move to the "Distances" tag. Click on "Search for Obj. Distances". Choose a search radius of 10 arcseconds. Then, click on "Mark all: Hipparccos". Click "Save Obj. Distances". Skip the "Extinction" tag.
  • Step5.- With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.
  • Step10.- The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. Bad photometric points can be removed cliking on "Delete". If VOSA detects an infrared excess, the photometric points are drawn in black and are not considered in the fitting process. The user can manually overrride it and specify a new limit in the "Apply excess from" panel. Do not make any modification to what VOSA shows in this page.
  • Step11.- In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params".
  • Step12.- In this window, we can refine the range of physical parameters that will be used for the fit. We will make the following assumption:
    • Nextgen: Teff: 2500-6000K; logg: 3.5-4.5
    • Dusty: Teff: 1800-2500K; logg: 3.5-4.5
    • COND: Teff: 100-1800K; logg: 3.5-4.5
    • Kurucz: Teff: 3500-6000K; logg: 3.5-4.5; met: 0
    • After this, click on "Make the fit".
  • Step13.- We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:
    • LOri0001: 4000K (Nextgen)
    • LOri0002: 3900K (Nextgen)
    • LOri0003: 4000K (Kurucz)
    • LOri0004: 3500K (Kurucz)
    • LOri0005: 4000K (Nextgen).
  • Step14.- Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, click "Make the fit". Do not make any restriction on the range of the physical parameters.
  • Step15.- For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).
  • Step16.- In order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. Nextgen isochrones and evol. tracks if Nextgen was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "Make the HR diagram".
  • Step17.- You can save different type of results (plots, VO photometry, Bayes fit, chi-2 fit,...) using the "Save Results" tag.
  • Step18.- A detailed description of how VOSA works can be found in the "Help" tag.

 
Deleted:
<
<
** Step 5: Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type.

** Step 6: In the new window, click on the radio button and then on "Select"

** Step 7: Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.

** Step8: We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.

** Step9: With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.

** Step10: The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. In this step the infrared excess automatically detected by VOSA can be changed by hand (see e.g. LOri003 or LOri004).

** Step11: In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params"

** Step12: In this window, we can refine the ranges of physical parameters that will be used for the fit. Given that we are working with cool stars we fix an upper limit of Teff=6000K for NextGen and Kurucz. Click on "Make the fit"

** Step13: We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:

* LOri0001: 4000K (Kurucz) * LOri0002: 3750K (Kurucz) * LOri0003: 4000K (Kurucz) * LOri0004: 3600K (Cond00) * LOri0005: 3900K (Cond00)

** Step14: Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, change the limits in Teff as we did in Step12 and click "Make the fit".

** Step15: For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).

** Step16: in order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. COND isochrones and evol. tracks if COND was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "MAke the HR diagram"

** Step17:

LOri001 83.446583 9.9273611 400. 0.36209598 CFHT_R 13.210000 0.0000000 LOri001 83.446583 9.9273611 400. 0.36209598 CFHT_I 12.520000 0.0000000 LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_J 11.297000 0.022000000 LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_H 10.595000 0.022000000 LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_Ks 10.426000 0.021000000 LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I1 10.228000 0.0030000000 LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I2 10.255000 0.0040000000 LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I3 10.214000 0.0090000000 LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I4 10.206000 0.010000000 LOri002 84.043167 10.148583 400. 0.36209598 CFHT_R 13.440000 0.0000000 LOri002 84.043167 10.148583 400. 0.36209598 CFHT_I 12.640000 0.0000000 LOri002 84.043167 10.148583 400. 0.36209598 2MASS_J 11.230000 0.024000000 LOri002 84.043167 10.148583 400. 0.36209598 2MASS_H 10.329000 0.023000000 LOri002 84.043167 10.148583 400. 0.36209598 2MASS_Ks 10.088000 0.019000000 LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I1 9.9350000 0.0030000000 LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I2 10.042000 0.0030000000 LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I3 9.9300000 0.0090000000 LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I4 9.8800000 0.0080000000 LOri003 83.981000 9.9420833 400. 0.36209598 CFHT_R 13.390000 0.0000000 LOri003 83.981000 9.9420833 400. 0.36209598 CFHT_I 12.650000 0.0000000 LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_J 11.416000 0.023000000 LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_H 10.725000 0.022000000 LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_Ks 10.524000 0.023000000 LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I1 10.262000 0.0030000000 LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I2 10.318000 0.0040000000 LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I3 10.239000 0.010000000 LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I4 10.171000 0.010000000 LOri004 83.948125 9.7640278 400. 0.36209598 CFHT_R 13.710000 0.0000000 LOri004 83.948125 9.7640278 400. 0.36209598 CFHT_I 12.650000 0.0000000 LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_J 11.359000 0.022000000 LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_H 10.780000 0.023000000 LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_Ks 10.548000 0.021000000 LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I1 10.287000 0.0030000000 LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I2 10.249000 0.0040000000 LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I3 10.185000 0.0090000000 LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I4 10.127000 0.0090000000 LOri005 83.473542 9.7188889 400. 0.36209598 CFHT_R 13.380000 0.0000000 LOri005 83.473542 9.7188889 400. 0.36209598 CFHT_I 12.670000 0.0000000 LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_J 11.378000 0.022000000 LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_H 10.549000 0.022000000 LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_Ks 10.354000 0.023000000 LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I1 10.204000 0.0030000000 LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I2 10.321000 0.0040000000 LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I3 10.218000 0.0090000000 LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I4 10.158000 0.0090000000 LOri006 83.817750 9.9216111 400. 0.36209598 CFHT_R 13.550000 0.0000000 LOri006 83.817750 9.9216111 400. 0.36209598 CFHT_I 12.750000 0.0000000 LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_J 11.542000 0.026000000 LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_H 10.859000 0.026000000 LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_Ks 10.648000 0.021000000 LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I1 10.454000 0.0030000000 LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I2 10.454000 0.0040000000 LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I3 10.399000 0.011000000 LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I4 10.319000 0.010000000 LOri007 83.623125 9.8163056 400. 0.36209598 CFHT_R 13.720000 0.0000000 LOri007 83.623125 9.8163056 400. 0.36209598 CFHT_I 12.780000 0.0000000 LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_J 11.698000 0.027000000 LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_H 11.101000 0.024000000 LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_Ks 10.895000 0.030000000 LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I1 10.668000 0.0040000000 LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I2 10.636000 0.0040000000 LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I3 10.615000 0.012000000 LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I4 10.482000 0.013000000 LOri008 83.991542 9.9091111 400. 0.36209598 CFHT_R 13.600000 0.0000000 LOri008 83.991542 9.9091111 400. 0.36209598 CFHT_I 12.790000 0.0000000 LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_J 11.548000 0.029000000 LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_H 10.859000 0.023000000 LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_Ks 10.651000 0.024000000 LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I1 10.498000 0.0030000000 LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I2 10.495000 0.0040000000 LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I3 10.440000 0.011000000 LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I4 10.256000 0.012000000 LOri009 83.693083 10.109889 400. 0.36209598 CFHT_R 13.700000 0.0000000 LOri009 83.693083 10.109889 400. 0.36209598 CFHT_I 12.950000 0.0000000 LOri009 83.693083 10.109889 400. 0.36209598 2MASS_J 11.843000 0.024000000 LOri009 83.693083 10.109889 400. 0.36209598 2MASS_H 11.109000 0.024000000 LOri009 83.693083 10.109889 400. 0.36209598 2MASS_Ks 10.923000 0.023000000 LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I1 10.834000 0.0040000000 LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I2 10.873000 0.0050000000 LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I3 10.788000 0.012000000 LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I4 10.743000 0.014000000 LOri010 83.637333 10.144750 400. 0.36209598 CFHT_R 13.700000 0.0000000 LOri010 83.637333 10.144750 400. 0.36209598 CFHT_I 12.960000 0.0000000 LOri010 83.637333 10.144750 400. 0.36209598 2MASS_J 11.880000 0.026000000 LOri010 83.637333 10.144750 400. 0.36209598 2MASS_H 11.219000 0.026000000 LOri010 83.637333 10.144750 400. 0.36209598 2MASS_Ks 11.041000 0.023000000 LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I1 10.916000 0.0040000000 LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I2 10.953000 0.0050000000 LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I3 10.733000 0.012000000 LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I4 10.839000 0.016000000

 back to main twiki page for the school

-- CarolineBot - 2011-02-07

Added:
>
>
-- EnriqueSolano - 2011-03-17

META FILEATTACHMENT attachment="vosa_usecase1.txt" attr="" comment="VOSA. Use Case #1. Data" date="1300367449" name="vosa_usecase1.txt" path="vosa_usecase1.txt" size="3367" user="EnriqueSolano" version="1"
META FILEATTACHMENT attachment="vosa_usecase2.txt" attr="" comment="VOSA. Use Case #2. Data" date="1300372813" name="vosa_usecase2.txt" path="vosa_usecase2.txt" size="180" user="EnriqueSolano" version="1"
 

Revision 22011-03-17 - EnriqueSolano

 
META TOPICPARENT name="ThematicTutorials"
  • Title: From SED fitting to Age estimation: The case of Collinder 69
Changed:
<
<
  • Tools to be used: VOSA
>
>
 
  • Data to be used: Here we will use a subset of the objects studied in Bayo, A. et al. ( 2008, A&A 492..277B). The list of objects in "VOSA format" is given below.
  • Workflow: The step-by-step use case can be found here
Added:
>
>
  • Use Case #1: Collinder 69 candidate members. Determination of physical parameters.
 
Changed:
<
<
    LOri001 83.446583 9.9273611 400. 0.36209598 CFHT_R 13.210000 0.0000000

>
>

Added:
>
>
**

** **

** Step 5: Upload the file in VOSA (tab Files). Give a description and do not forget to select "magnitudes" as file type.

** Step 6: In the new window, click on the radio button and then on "Select"

** Step 7: Click on "Objects" (next tag). You will see a table with three columns: The name of our objects (first column in the input file), the coordinates provides by the user (second and thrid column of the input file) and a third column where the coordinates provided by Sesame will appear once we click on "Search for obj. coordinates". As our object identifiers are meningless (LOri001, LOri002,...) we will not use the Sesame capabilities.

** Step8: We skip the "Distances" and "Extinction" tags as the VO services consulted by VOSA do not provide any information for our list of objects.

** Step9: With the next tag "VO Phot" we can complement our "user photometry" with photometry found in a number of VO services. For this use case we select only 2MASS and CMC-14. Do not forget to click on "Save VO photometry" once the results are displayed. Once this is done, a summary table with the VO photometry (in flux units) will appear.

** Step10: The next tag ("SED") gives us the possibility of checking the SED before the model fitting. User data are plotted in red and VO data in green. In this step the infrared excess automatically detected by VOSA can be changed by hand (see e.g. LOri003 or LOri004).

** Step11: In the next tag ("Model Fit"), a list of collection of theoretical models is provided. They cover different ranges of physical parameters. For this case, we select the "Nextgen", "Dusty","Cond" and "Kurucz" set of models. Click on "Select model params"

** Step12: In this window, we can refine the ranges of physical parameters that will be used for the fit. Given that we are working with cool stars we fix an upper limit of Teff=6000K for NextGen and Kurucz. Click on "Make the fit"

** Step13: We can see now a summary table with the best fit results. Click on "Show graphs" to have a look at the graphics. The effective temperatures obtained after the fitting would be:

* LOri0001: 4000K (Kurucz) * LOri0002: 3750K (Kurucz) * LOri0003: 4000K (Kurucz) * LOri0004: 3600K (Cond00) * LOri0005: 3900K (Cond00)

** Step14: Alternatively to the chi2-fitting you can perform a Bayesian fitting using the "Bayes analysis" tag. To do so, we select the same collection of models as in Step11 and click on "Select model params". Then, change the limits in Teff as we did in Step12 and click "Make the fit".

** Step15: For every collection of models and every physical parameter, a summary table with information on the model wit the highest probability is shown. For each object, the information is graphically displayed by clicking on the object name (top left panel).

** Step16: in order to estimate ages and masses for our objects we will make use of the "HR Diag." tab. The isochrones and evolutionary tracks to be used depend on the best fit model (e.g. COND isochrones and evol. tracks if COND was the best model). By clicking on "See list of objects" you can see the relationship between objects and tracks/isochrones. Then, click on "MAke the HR diagram"

** Step17:

LOri001 83.446583 9.9273611 400. 0.36209598 CFHT_R 13.210000 0.0000000

  LOri001 83.446583 9.9273611 400. 0.36209598 CFHT_I 12.520000 0.0000000 LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_J 11.297000 0.022000000 LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_H 10.595000 0.022000000 LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_Ks 10.426000 0.021000000 LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I1 10.228000 0.0030000000 LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I2 10.255000 0.0040000000 LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I3 10.214000 0.0090000000 LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I4 10.206000 0.010000000 LOri002 84.043167 10.148583 400. 0.36209598 CFHT_R 13.440000 0.0000000 LOri002 84.043167 10.148583 400. 0.36209598 CFHT_I 12.640000 0.0000000 LOri002 84.043167 10.148583 400. 0.36209598 2MASS_J 11.230000 0.024000000 LOri002 84.043167 10.148583 400. 0.36209598 2MASS_H 10.329000 0.023000000 LOri002 84.043167 10.148583 400. 0.36209598 2MASS_Ks 10.088000 0.019000000 LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I1 9.9350000 0.0030000000 LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I2 10.042000 0.0030000000 LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I3 9.9300000 0.0090000000 LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I4 9.8800000 0.0080000000 LOri003 83.981000 9.9420833 400. 0.36209598 CFHT_R 13.390000 0.0000000 LOri003 83.981000 9.9420833 400. 0.36209598 CFHT_I 12.650000 0.0000000 LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_J 11.416000 0.023000000 LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_H 10.725000 0.022000000 LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_Ks 10.524000 0.023000000 LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I1 10.262000 0.0030000000 LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I2 10.318000 0.0040000000 LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I3 10.239000 0.010000000 LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I4 10.171000 0.010000000 LOri004 83.948125 9.7640278 400. 0.36209598 CFHT_R 13.710000 0.0000000 LOri004 83.948125 9.7640278 400. 0.36209598 CFHT_I 12.650000 0.0000000 LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_J 11.359000 0.022000000 LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_H 10.780000 0.023000000 LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_Ks 10.548000 0.021000000 LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I1 10.287000 0.0030000000 LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I2 10.249000 0.0040000000 LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I3 10.185000 0.0090000000 LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I4 10.127000 0.0090000000 LOri005 83.473542 9.7188889 400. 0.36209598 CFHT_R 13.380000 0.0000000 LOri005 83.473542 9.7188889 400. 0.36209598 CFHT_I 12.670000 0.0000000 LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_J 11.378000 0.022000000 LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_H 10.549000 0.022000000 LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_Ks 10.354000 0.023000000 LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I1 10.204000 0.0030000000 LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I2 10.321000 0.0040000000 LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I3 10.218000 0.0090000000 LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I4 10.158000 0.0090000000 LOri006 83.817750 9.9216111 400. 0.36209598 CFHT_R 13.550000 0.0000000 LOri006 83.817750 9.9216111 400. 0.36209598 CFHT_I 12.750000 0.0000000 LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_J 11.542000 0.026000000 LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_H 10.859000 0.026000000 LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_Ks 10.648000 0.021000000 LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I1 10.454000 0.0030000000 LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I2 10.454000 0.0040000000 LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I3 10.399000 0.011000000 LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I4 10.319000 0.010000000 LOri007 83.623125 9.8163056 400. 0.36209598 CFHT_R 13.720000 0.0000000 LOri007 83.623125 9.8163056 400. 0.36209598 CFHT_I 12.780000 0.0000000 LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_J 11.698000 0.027000000 LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_H 11.101000 0.024000000 LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_Ks 10.895000 0.030000000 LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I1 10.668000 0.0040000000 LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I2 10.636000 0.0040000000 LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I3 10.615000 0.012000000 LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I4 10.482000 0.013000000 LOri008 83.991542 9.9091111 400. 0.36209598 CFHT_R 13.600000 0.0000000 LOri008 83.991542 9.9091111 400. 0.36209598 CFHT_I 12.790000 0.0000000 LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_J 11.548000 0.029000000 LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_H 10.859000 0.023000000 LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_Ks 10.651000 0.024000000 LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I1 10.498000 0.0030000000 LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I2 10.495000 0.0040000000 LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I3 10.440000 0.011000000 LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I4 10.256000 0.012000000 LOri009 83.693083 10.109889 400. 0.36209598 CFHT_R 13.700000 0.0000000 LOri009 83.693083 10.109889 400. 0.36209598 CFHT_I 12.950000 0.0000000 LOri009 83.693083 10.109889 400. 0.36209598 2MASS_J 11.843000 0.024000000 LOri009 83.693083 10.109889 400. 0.36209598 2MASS_H 11.109000 0.024000000 LOri009 83.693083 10.109889 400. 0.36209598 2MASS_Ks 10.923000 0.023000000 LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I1 10.834000 0.0040000000 LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I2 10.873000 0.0050000000 LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I3 10.788000 0.012000000 LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I4 10.743000 0.014000000 LOri010 83.637333 10.144750 400. 0.36209598 CFHT_R 13.700000 0.0000000 LOri010 83.637333 10.144750 400. 0.36209598 CFHT_I 12.960000 0.0000000 LOri010 83.637333 10.144750 400. 0.36209598 2MASS_J 11.880000 0.026000000 LOri010 83.637333 10.144750 400. 0.36209598 2MASS_H 11.219000 0.026000000 LOri010 83.637333 10.144750 400. 0.36209598 2MASS_Ks 11.041000 0.023000000 LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I1 10.916000 0.0040000000 LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I2 10.953000 0.0050000000 LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I3 10.733000 0.012000000 LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I4 10.839000 0.016000000

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-- CarolineBot - 2011-02-07

Revision 12011-02-07 - CarolineBot

 
META TOPICPARENT name="ThematicTutorials"
  • Title: From SED fitting to Age estimation: The case of Collinder 69
  • Tools to be used: VOSA
  • Data to be used: Here we will use a subset of the objects studied in Bayo, A. et al. ( 2008, A&A 492..277B). The list of objects in "VOSA format" is given below.
  • Workflow: The step-by-step use case can be found here

    LOri001 83.446583 9.9273611 400. 0.36209598 CFHT_R 13.210000 0.0000000
    LOri001 83.446583 9.9273611 400. 0.36209598 CFHT_I 12.520000 0.0000000
    LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_J 11.297000 0.022000000
    LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_H 10.595000 0.022000000
    LOri001 83.446583 9.9273611 400. 0.36209598 2MASS_Ks 10.426000 0.021000000
    LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I1 10.228000 0.0030000000
    LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I2 10.255000 0.0040000000
    LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I3 10.214000 0.0090000000
    LOri001 83.446583 9.9273611 400. 0.36209598 IRAC_I4 10.206000 0.010000000
    LOri002 84.043167 10.148583 400. 0.36209598 CFHT_R 13.440000 0.0000000
    LOri002 84.043167 10.148583 400. 0.36209598 CFHT_I 12.640000 0.0000000
    LOri002 84.043167 10.148583 400. 0.36209598 2MASS_J 11.230000 0.024000000
    LOri002 84.043167 10.148583 400. 0.36209598 2MASS_H 10.329000 0.023000000
    LOri002 84.043167 10.148583 400. 0.36209598 2MASS_Ks 10.088000 0.019000000
    LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I1 9.9350000 0.0030000000
    LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I2 10.042000 0.0030000000
    LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I3 9.9300000 0.0090000000
    LOri002 84.043167 10.148583 400. 0.36209598 IRAC_I4 9.8800000 0.0080000000
    LOri003 83.981000 9.9420833 400. 0.36209598 CFHT_R 13.390000 0.0000000
    LOri003 83.981000 9.9420833 400. 0.36209598 CFHT_I 12.650000 0.0000000
    LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_J 11.416000 0.023000000
    LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_H 10.725000 0.022000000
    LOri003 83.981000 9.9420833 400. 0.36209598 2MASS_Ks 10.524000 0.023000000
    LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I1 10.262000 0.0030000000
    LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I2 10.318000 0.0040000000
    LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I3 10.239000 0.010000000
    LOri003 83.981000 9.9420833 400. 0.36209598 IRAC_I4 10.171000 0.010000000
    LOri004 83.948125 9.7640278 400. 0.36209598 CFHT_R 13.710000 0.0000000
    LOri004 83.948125 9.7640278 400. 0.36209598 CFHT_I 12.650000 0.0000000
    LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_J 11.359000 0.022000000
    LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_H 10.780000 0.023000000
    LOri004 83.948125 9.7640278 400. 0.36209598 2MASS_Ks 10.548000 0.021000000
    LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I1 10.287000 0.0030000000
    LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I2 10.249000 0.0040000000
    LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I3 10.185000 0.0090000000
    LOri004 83.948125 9.7640278 400. 0.36209598 IRAC_I4 10.127000 0.0090000000
    LOri005 83.473542 9.7188889 400. 0.36209598 CFHT_R 13.380000 0.0000000
    LOri005 83.473542 9.7188889 400. 0.36209598 CFHT_I 12.670000 0.0000000
    LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_J 11.378000 0.022000000
    LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_H 10.549000 0.022000000
    LOri005 83.473542 9.7188889 400. 0.36209598 2MASS_Ks 10.354000 0.023000000
    LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I1 10.204000 0.0030000000
    LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I2 10.321000 0.0040000000
    LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I3 10.218000 0.0090000000
    LOri005 83.473542 9.7188889 400. 0.36209598 IRAC_I4 10.158000 0.0090000000
    LOri006 83.817750 9.9216111 400. 0.36209598 CFHT_R 13.550000 0.0000000
    LOri006 83.817750 9.9216111 400. 0.36209598 CFHT_I 12.750000 0.0000000
    LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_J 11.542000 0.026000000
    LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_H 10.859000 0.026000000
    LOri006 83.817750 9.9216111 400. 0.36209598 2MASS_Ks 10.648000 0.021000000
    LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I1 10.454000 0.0030000000
    LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I2 10.454000 0.0040000000
    LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I3 10.399000 0.011000000
    LOri006 83.817750 9.9216111 400. 0.36209598 IRAC_I4 10.319000 0.010000000
    LOri007 83.623125 9.8163056 400. 0.36209598 CFHT_R 13.720000 0.0000000
    LOri007 83.623125 9.8163056 400. 0.36209598 CFHT_I 12.780000 0.0000000
    LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_J 11.698000 0.027000000
    LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_H 11.101000 0.024000000
    LOri007 83.623125 9.8163056 400. 0.36209598 2MASS_Ks 10.895000 0.030000000
    LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I1 10.668000 0.0040000000
    LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I2 10.636000 0.0040000000
    LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I3 10.615000 0.012000000
    LOri007 83.623125 9.8163056 400. 0.36209598 IRAC_I4 10.482000 0.013000000
    LOri008 83.991542 9.9091111 400. 0.36209598 CFHT_R 13.600000 0.0000000
    LOri008 83.991542 9.9091111 400. 0.36209598 CFHT_I 12.790000 0.0000000
    LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_J 11.548000 0.029000000
    LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_H 10.859000 0.023000000
    LOri008 83.991542 9.9091111 400. 0.36209598 2MASS_Ks 10.651000 0.024000000
    LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I1 10.498000 0.0030000000
    LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I2 10.495000 0.0040000000
    LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I3 10.440000 0.011000000
    LOri008 83.991542 9.9091111 400. 0.36209598 IRAC_I4 10.256000 0.012000000
    LOri009 83.693083 10.109889 400. 0.36209598 CFHT_R 13.700000 0.0000000
    LOri009 83.693083 10.109889 400. 0.36209598 CFHT_I 12.950000 0.0000000
    LOri009 83.693083 10.109889 400. 0.36209598 2MASS_J 11.843000 0.024000000
    LOri009 83.693083 10.109889 400. 0.36209598 2MASS_H 11.109000 0.024000000
    LOri009 83.693083 10.109889 400. 0.36209598 2MASS_Ks 10.923000 0.023000000
    LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I1 10.834000 0.0040000000
    LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I2 10.873000 0.0050000000
    LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I3 10.788000 0.012000000
    LOri009 83.693083 10.109889 400. 0.36209598 IRAC_I4 10.743000 0.014000000
    LOri010 83.637333 10.144750 400. 0.36209598 CFHT_R 13.700000 0.0000000
    LOri010 83.637333 10.144750 400. 0.36209598 CFHT_I 12.960000 0.0000000
    LOri010 83.637333 10.144750 400. 0.36209598 2MASS_J 11.880000 0.026000000
    LOri010 83.637333 10.144750 400. 0.36209598 2MASS_H 11.219000 0.026000000
    LOri010 83.637333 10.144750 400. 0.36209598 2MASS_Ks 11.041000 0.023000000
    LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I1 10.916000 0.0040000000
    LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I2 10.953000 0.0050000000
    LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I3 10.733000 0.012000000
    LOri010 83.637333 10.144750 400. 0.36209598 IRAC_I4 10.839000 0.016000000

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-- CarolineBot - 2011-02-07

 
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