Use case: interpreting structure of X-Ray clusters

Description

A user has obtained and analysed a detailed X-Ray image of a galaxy cluster and derived temperature and pressure maps from them (see for example Schuecker et al, 2004). Using locally developed statistical techniques small scale sub-structure is investigated and an interpretation in terms of a turbulent intra cluster medium is proposed. To investigate whether this interpretation is realistic a similar analysis is desired on simulated images. This requires availability of hydro simulations of galaxy clusters with the appropriate physics included and services that can create mock temperature and pressure images from this simulation. For an example of such a service see the GAVO website.

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primary actor

X-Ray astronomer

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End result:

Mock temnperature and pressure images are obtained from simulated galaxy cluster ready for comparison to real X-Ray observations.

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Other actors:

Simulator

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Pre-conditions

1. A registry searchable for simulations filtered on physical properties and services for producing images.
2. Appropriate standards for defining the datasets and services (to be defined what "appropriate" means).
3. An environment allowing configuration and execution of the services.
4. Standards for data transfer formats.

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Flow of events

1. User browses registry for appropriate virtual telescope service based on simulation and service meta-data
2. Selects service and provides input
3. Service executes and provides (links to) results

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Post-condition

1. Mock images provided in standardized format, for example FITS

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Basic assumptions

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Alternative flows

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Key references

1. Probing turbulence in the Coma Galaxy cluster (ADS, astro-ph)
   Schuecker P. et al, 2004
   Astronomy and Astrophysics, v.426, p.387-397

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Requirements on IVOA working goups

• G&WS: provide VO compatible infrastructure for this kind of services.
• Registry: allow registration of this kind of service in such a way that user does not need to browse 12000 items in registry to find them: allow querying on resource(?) model that is rich enough to filter out desired simulations with their services.
• DM: allow phenomenological characterization of published simulation snapshots.

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Please add comments below. This area should be used for refinement of the above document. If you want to ask questions or start a dialogue with the author, please use the theory mailing list.

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-- GerardLemson - 20 Sep 2005