REGISTRY KEYWORDS

As a preliminary attempt I have set up a namespace for keywords based on the Vizier list. Ideally there would be an internationally agreed namespace based on the IAU Thesaurus. However at present that is very out of date. The Vizier list is based on a sub-set of ADC keywords (see **) and is designed to describe dataSets (as distinct from the journal keywords, *, which describe science goals).

The list will need additions to cover solar and STP as well as non-dataSet entries. I suggest that the first step should be to check the ADC, Journal and IAU lists above to see if a new word can be drawn from them. I also suggest that we keep the list as short, simple and general as possible and in general terms should be added cautiously:

• If there are no existing keywords at all relevant to an entry (e.g. 'community' descriptions);
• If a use case produces a poor or unwieldy result which could be avoided if a suitable keyword had appeared (e.g. Open_Cluster and Proper_Motion will help the Brown Dwarf case);
• They should be self-explanatory at least to someone with a general knowledge of astronomy/solar/STP/VO work, so that they can be used to search the Registry without referring to yet another namespace.

• For individual instances of objects e.g. Stars-(S Per) (these are allowed in Journal keywords) - however exceptions may be needed e.g. "Sun";
• If they are covered elswhere in the Registry e.g. instruments (unless we find we want to enter a data base of instruments);

We may also want to weed some of these keywords; for example Photometry:intermediate_band etc. may be too esoteric to be useful (and covered elswhere in coverageSpectral etc.) - however a keyword like Photometric_Standards might be useful.

For ease of interpreting data-provider entries and checking syntax I suggest that the keywords should follow the convention below i.e. include a-z A-Z _ : + - but no spaces. The capitalisation conventions below should be followed but no keyword should depend on it.

Comments not in "" are my attempt at explanations for non-astronomers. If anything is not adequate please either correct or add a ? Note that some keywords describe observational phenomena which could result from or be applied to many kinds of object; others are observational classes of object (e.g. Seyfert galaxies) and yet others are deduced phenomena e.g. gravitional lenses.

Please add new keywords in green and comments in purple

-- AnitaRichards - 13 Aug 2003