1. Metadata for the Registry Anita Richards JBO/AVO/AstroGrid Registry extracts and stores minimum information to select catalogues which might be relevant ● From headers (e.g. telescope) ● From entries (e.g. coverage) DataSet ID ListData header nDimData header Archive catalogues col. col. UCD UCD row value value col. col. UCD UCD row value link to link to value image SED server plot value link to link to value image SED server plot Registry Extracted via UCDs

2. Describing catalogues ● Registry requirements becoming well-developed: – IVOA & constituent forums ● AstroGrid etc. working groups – Derriere, Hanisch documents etc. etc. ● How do we extract the information from – tables – source catalogues – archive catalogues etc? ● UCDs needed for – Data-providers' header information – Coverage and other info extracted from catalogues – Evaluation/ defaults for missing info e.g. epoch

3. What UCDs? e.g. frequency... ● Potential observations in these instrumental bands – FREQ_RADIO? or FREQ (value radio)? ● Possible bins allocated by VO – FREQ_COVERAGE (list or matrix must be evaluated) ● Resolution - from finest possible to greatest continuous bandwidth for a single observation – FREQ_RESOLUTION_FINE / _COARSE? – or FREQ_RESOLUTION (value broadest, narrowest) – translate ambiguities e.g. 'max/min', Ha (what velocity) 1.0 2.0 4.0 8.0 16.0 32.0 MHz 1kHz chans 50 MHz total obs bandwidth 1 2 3 4 5

4. What UCDs? e.g. frequency... ● Data quality - bandpass function exists, errors etc. – FREQ_QUALITY_WELLDEFINED (by provider) – or FREQ_QUALITY_DEFAULT (VO assigned) ● Other header information not for Registry but needed to answer query e.g. – all observations at 1.4 GHz - propagate header UCD FREQ_1.4G to all columns? – Bandpass look-up table 1.0 2.0 4.0 8.0 16.0 32.0 MHz 1kHz chans 50 MHz total obs bandwidth

5. Developing Registry UCDs ● Sebastien Derriere's paper – Section 3 - Data Models - top levels inform Registry – Section 4 - UCDs must be according to controlled vocabulary and etymology ● FREQ_COVERAGE or COVERAGE_FREQ? ● Evolve with respect to demand – Data providers ● CDS contains >2500 optical catalogues, 2 eUV – Registry finer-grained in optical regime – Science use cases ● AVO Demo (e.g. select catalogues with PHOTOMETRY) ● Brown Dwarf case etc. etc.