1. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 1 DALIA : an observation vs simulation comparison frame work What could be a Model of simulation code worth for ? What could be a Model of simulation code worth for ? Frédéric Boone Mireille Louys Marie-Lise Dubernet François Bonnarel Nicolas Moreau

2. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 2 Motivation Standardize description of numerical codes used to modelize astronomical objects Specify all the information required by a user to run the code: inputs, outputs, control parameters Adjust Simulation codes parameters in iterations for simulated and observed data comparisons and interpretation

3. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 3 A generic framework for modeling Graphical User Interface (Web Service) model codes Observations spectroscopic data Best fit parameters with error bars Optimization engine Use existing formats and visualization tools Define a standard Query existing databases Use existing algorithms

4. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 4 DALIA

5. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 5 DALIA within the VO Old data from archives New observations Old optimal model instance from archives Model code (algorithm) from archives

6. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 6 DALIA

7. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 7 Code Example a code that simulates observations of a galactic disk –it takes some parameters as input –It produces a data cube (position, position, velocity) of flux density for a given molecular or atomic transition (e.g. Halpha, CO(1-0),...) To allow a user (or an application) to use the code (run it and read the outputs) the code “provider” needs to describe the various kind of metadata

8. Different types of information required Inputs related to the astrophysical source inclination, size of disk etc... Inputs related to the algorithm used in the code number of particles Inputs related to instrumental effects psf, sampling, etc... Inputs related to general knowledge in physics frequency(ies) of the transition(s) considered (Halpha or CO etc...) for the emission Output dataset(s) number of axes, nature of axes,... Characterisation or Spectrum data models Simulation Model Characterisation, Lev 1-4 Atomic Line data model Simulation

9. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 9 Parameter Model Requirements To structure the parameter set (Sections, Subsections...) --> The code provider may structure the parameters according to their physical meaning to help the user to catch the physics behind Allow for dynamical description –Hierarchy (a parameter determines a subset of parameters) –Tables (several parameters can be vectors of variable length) Allow information on the numerical code (program) to be included (native language, variable names used in the code) --> help user/application to implement protocol for data exchange with code (generate pieces of codes in the native language)

10. The UML Schema Objects to describe dynamical parameter sets Objects to structure the description of parameter sets

11. Three levels of documents LevelLevel descriptionDescription fileWho is preparing it How it is used Parameter collection List of parameter values for one single code execution nuagemoleculaire.dal generated via the GUI by the interface generator of Dalia By the user, via a gui or by editing a template xml document Launched by either a user or a workflow Xml template document for one code Structure and description of code parameters for one code (tree + table combinations) nuagemoleculaire.xml The « Code provider » when publishing the code in a registry By the Dalia interface generator application for instance General XML schema Overall structure of possible parameters in any simulation code astronumericalcodes.xsd Up to the Theory IG to validate and/or generalise it By a parser to validate new descriptions of simulation codes

12. Structured parameter set Situation Coordinates RA ra hh:mm:s Right Ascension of dynamic center -10:40:20.00 Dec dec dd:mm:s Declination of dynamic center 20:40:00.00 UMLXML INSTANCEDALIA GUI

13. Potential type pottype Potential shape Logarithmic Length scale rp pc Length scale of potential 200 Velocity scale vp km/s velocity scale of potential 100 Plummer Length scale Hierarchy in a dynamical parameter set UMLXML INSTANCEDALIA GUI

14. Radial distribution Radial distribution of matter nur radius radius uradii pc Radius in pc 100. Col. Dens. udens 10^22 cm-2 Comlumn density 1. Vel. Disp. udisp km/s Velocity dispersion 10. Dynamical table of parameters UMLXML INSTANCE DALIA GUI

15. Mireille Louys et al., OV-France Theory WG meeting, LYON, June 2007 15 Perspectives Commonalities with the Simulation model Distribute the intermediate level (mybeautifulmodel.xml) + an interface generator Share « instances » of models in the sense of an instance of parameter set: –e.g. result of a model fit = values of the best fit parameters --> need to define a data model for instances of parameter sets –How do we allow simple identification of output matching between snapshot and observation ? –Jargon translation ? ==> how to share theoretical knowledge at the same level as the observations