New UCD list

[Jonathan McDowell]

Dear Andrea,
 I've been looking at the new UCD list. I have a question, some comments and a
concern.

question: I assume that the suggestion I made in Aug 2004 for "phot.flux.beam" 
 should now be handled by "phot.flux;instr.beam" using the new "instr.beam"
 UCD?

comment: I applaud the simplification of phot.color. How are you handling
this in the Vizier tables with more than one color? Adding secondary pairs of
"em.*" UCDs?

comment: The UCD desc for 'phot.count' still includes the comment "count (/s)"
even though on Oct 19 you agreed on the feedback form that we drop the "/s".

comment: I second Alberto's suggestions on homogenization of things like
resolution. 

comment: However, On attempting to map the WCS keywords with things like
arith.1_1, I think this is trying to take UCDs beyond where they should
go (something I've been accused of myself!). That's what a UTYPE is for,
to map it to a data model. All the components of cdmatrix are the same
kind of thing and should have the same ucd. 

concern:

On the comments page I also asked in August-Sept. 2004 for feedback on the
following proposed UCDs:
  em.veloc.radio
  meta.curation
  phys.energy-density
  src.net

I'm a bit disappointed that many months later a new list has emerged
without none of these being addressed, even with a "well, I don't think
this is sensible for a UCD". These were proposed not just for fun, but
as things needed for the spectral data model document. I also still
think that it would be a good idea if new UCDs were circulated for
comment to the UCD WG "board" before the web page was updated, the
process still seems a bit opaque and over-centralized.

(by the way, the automated emails we get with "A suggestion has been made for
a new UCD" would I think be much more useful if the text of the suggestion
was included, removing one step in the process, since I have the impression
few WG members have been responding to them).

  Best wishes,
     Jonathan McDowell