Review of VO Science Cases in Relation to VO Registries. -------------------------------------------------------- v1.0 M.Allen. April 11, 2003. A goal of RWP02 is to identify Key Science Cases to be used as drivers for defining registry requirements. These should be illustrative of the range of requests that may be sent to a registry. These notes are an attempt to review the current science cases from the various VO initiatives, in relation to VO registries. Some of the individual groups have already made some assessment of their science cases with respect to registries, and these notes draw directly from those assessments. I've paraphrased the various cases, and made short notes with respect to registries. This is really a first pass, and may sometimes border on statements of the obvious, so please feel free to comment or change anything here. List of Current VO Science Cases: --------------------------------- * AstroGrid * AstroGrid has a fairly well developed set of science cases including sequence diagrams described on the follow pages: http://wiki.astrogrid.org/bin/view/Astrogrid/ScienceProblems http://wiki.astrogrid.org/bin/view/Astrogrid/SequenceDiagrams 1. Brown Dwarf Selection 2. Deep Field Surveys 3. Galaxy Clustering 4. Hi-Z Quasars 5. Low Surface Brightness Galaxy Discovery 6. Magnetic Storm Onset 7. Solar Coronal Waves 8. Solar Stellar Flare Comparison 9. STP Solar Event Coincidence 10. Supernova Galaxy Environment * NVO * NVO developed a number of science drivers for their demos, and also have a number of Registry Science/Use Cases posted to the Registry mail list. (N.Gaffney) 1. Find Super Novae Pre-Burst Observations 2. Select Dwarf Galaxies by Colour for Observational Follow-up 3. Construct Highest Signal-to-Noise V-band image of sky region (T.McGlynn) 1. Find all object catalogs derived from a mission 2. Find queriable image-cutout services with sky coverage and galactic coordinate criteria. Gamma Ray Burst Demo + Other demo cases... * AstroVirtel * AstroVirtel have a draft document on the registry relevant aspects of one of their current science cases: Luminosity functions of Star Clusters in Nearby Galaxies (De Grijs). The document is on the wiki at http://www.ivoa.net/internal/IVOA/RegistryUseCases/astrovirtel_use_case.pdf (A.Micol) * AVO demo science case * This science case was related to finding red objects in the GOODS data. The demo used the GLU as implemented with a customized Aladin and a VOTABLE metadata tree that works a bit like a registry, but perhaps this is more related to data model issues. (A general meta-data tree function for Aladin is to be announced on the DM mailing list very soon) Notes on the Current Science Cases with respect to Registries: -------------------------------------------------------------- * AstroGrid * This is taken directly from their sequence diagrams where "resource catalog" is taken to mean Registry. (is that correct?) 1. Brown Dwarf Selection * Search the resource catalog for catalogs containing Galactic clusters - Registry needs to be able to identify resources which provide catalogs, and be able to find those relevant to "Galactic Clusters" * Query registry for catalogs with coverage of I, K, or R wavelengths over each cluster location - Registry needs to be able to select catalogs based on wavelength and spatial coverage - In general the registry is expected to return lists of catalogs 2. Deep Field Surveys * Search the resource catalog for optical and radio deep field surveys with wavelength, instrument, sensitivity, dynamic range, epoch, and resolution metadata. A list of surveys is returned and one or more are selected - Registry needs to be able to identify deep field surveys - Registry needs observation specific info: instrument, sensitivity, dynamic range, resolution - Registry needs epoch or temporal coverage information - Registry is assumed to return lists of surveys/catalogs with the possibility of making selections from these. 3. Galaxy Clustering * Search the registry for galaxy catalogs. - Registry needs to be able to identify galaxy catalogs * After selecting sources, search the registry for a spectrographic catalog to query by coordinates. - Registry needs to be able to identify resources with spectral catalogs, and say whether those catalogs can be queried by coordinates 4. Hi-Z Quasars * This case is focused on using large surveys - Registry required to locate those survey resources, and provide information on how they can be queried. 5. Low Surface Brightness Galaxy Discovery * Locate large scale structure with low contrast to background - Registry needed to locate surveys, how to query them... 6. Magnetic Storm Onset * Locate an on-line source of data for that spacecraft and request data for a time window around each magnetic storm. - Registry required to locate data source, and whether it can query with temporal parameters. 7. Solar Coronal Waves 8. Solar Stellar Flare Comparison 9. STP Solar Event Coincidence 10. Supernova Galaxy Environment * Search literature and published sources for possible spectroscopic redshifts of galaxies in fields. - Registry provides location of publication resources, and how to query them for keywords like "galaxy" and "redshift" * Search archives for spectroscopic data of objects in field - Registry needs to identify spectroscopic databases - Registry needs spatial coverage information for databases * NVO * 1. Find Super Novae Pre-Burst Observation * get all IR, Optical, and UV data (derived photometry or images or spectra) from any data source that may have been observing it during a specified time period - Registry required to locate all data at a given point, i.e. spatial and temporal coverage * get all observations that have a chance of detecting/resolving it - Registry would need sensitivity and resolution information about observational data. 2. Select Dwarf Galaxies by Colour for Observational Follow-up * get colors U-K and R-H (either colors, magnitudes, or data from which magnitudes can be extracted in that order) for dwarf galaxies with known V magnitudes and redshift or absolute V magnitudes - Registry needs to identify catalogs of dwarf galaxies, and whether they contain colour or magnitude measurements * I would like to know which services that provide the colors I need are based on other data in the VO, so I don't redo the color measurement when I don't have to - Requires knowledge of provenance of data in catalogs 3. Construct Highest Signal-to-Noise V-band image of sky region * need all independent observations (e.g. not based on the same raw data) at V of this area of the sky that have a resolution and pixel size on the sky of at least 1 and 0.5 arcseconds respectively - Registry needs to identify independent obs in a region of sky - Requires resolution and pixel size information of registered archives. 4. Gamma Ray burst + Not detailed here, but RayPlante says he'll: "Summarize how a registry will be incorporated into the NVO Gamma Ray Burster demo (making it a general-purpose "show me the sky" tool)." * AstroVirtel * Alberto's document provides quite a lot of detail from their practical experience of running VO-like science cases. Here I've tried to make a summary for general consumption. Types of Service identified within a Registry -------------------------------------------- The AstroVirtel use case scenario identifies requirements for registries, in terms of the types of services a registry should be able to identify. The types specific to the given example scenario are - Catalog Browser Services - e.g. a catalog search engine like VizieR - Services relating to a particular class of astronomical objects, e.g. Galaxies - Services providing particular types of data, e.g. Astronomical Object Catalogs, Image Data - Services that directly provide particular output parameters e.g galaxy name ID, galaxy position, galaxy type - Services that can be constrained by a given parameter, such as distance. Further, registered services should give some idea of the - number of records available - wavelength or passband coverage - minimum resolution - calibration status of data