VOtheorySynthesis < IVOA

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<H1>Use case: Comparison/use of evolutionary synthesis models</H1>
<H2>Description</H2>

_Case A_: A user with deep knowledge of evolutionary synthesis models wants to compare the 
results given by different grids of models (produced by different developers/groups) for the same set of input parameters.

_Case B_: A user wants to retrieve an specific evolutionary synthesis model to perform a simple comparison (overplot) with real data. 
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<H2>primary actor</H2>
_Case A_: Evolutionary synthesis model expert user

_Case B_: Evolutionary synthesis model standard user
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<H2>End result:</H2>

_Case A_: Plot by VOSpec of results obtained from different grids of models with the same 
input parameters (age and metallicity).

_Case B_: Plot by VOSpec of results of theoretical and real data.

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<H2>Other actors:</H2>

_Case A_: Evolutionary synthesis model server

_Case B_: Evolutionary synthesis model server, observational data server

- VOSpec
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<H2>Pre-conditions</H2>

1 Existence of a protocol (e.g. TSAP) that explores (using the "format=metadata" option) 
the parameter space of the theoretical grid (not known a priori). 
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<H2>Flow of events</H2>

All the information exchange between the synthesis model server and VOSpec is done using the TSAP protocol.

_Case A_:

   1 User logins in VOSpec and selects the corresponding service.
   2 In response to the "format=metadata" query, the service sends a VOTable to VOSpec with the parameter space (and the associated valid values) that defines the grid of models.
   3 The user selects the desired parameters/values, and VOSpec send them back to the service.
   4 The service returns a VOTable with the results to be displayed by VOSpec. Depending on the server, the results can be obtained from a pre-computed grid of models or on-the-fly. 

_Case B_ (includes Case A, plus):

   5 The user chooses an spectroscopic observation with VOSpec.
   6 Models and observations are plotted and normalized to a common scale.
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<H2>Post-condition</H2>
   1 Results provided in VOTable format
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<H2>Basic assumptions</H2>

   Synthesis models mix the results of two types of theoretical results: evolutionary tracks and atmosphere models.

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<H2>Alternative flows</H2>

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<H2>Open Issues</H2>

   1 How to evaluate if the resulting model (final product of a mathematical algorithm) has a physical meaning? Use of cautions, warnings etc...?  

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Originally sent by *M. Cerviño - 27 Sep 2005* <br>
Last modified: *E. Solano - 28 Sep 2005*
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This area should be used for refinement of the above document. If you want to ask questions or start a dialogue with the author, 
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This topic: IVOA > VOtheorySynthesis
Topic revision: r3 - 2005-09-28 - EnriqueSolano