[Radioig] ObsCore Extension For Radio Data discussion

[Mark Kettenis]

Agenda for discussion on IVOA Obscore Extension for Radio data

Tuesday July 2, 15:30-16:30 UTC (17:30-18:30 CEST)

Zoom coordinates:

https://astron.zoom.us/j/81533464364?pwd=bQh0hVs3x3kAmjaLbwoDNJsjIFyIWS.1

Meeting ID: 815 3346 4364
Passcode: 354277


Agenda
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1. Representation of the ObsCore extension:

  The PR standardizes a new ivoa.obscore_radio table and mandates the
  presence of a obs_publisher_did column in order to be able to do a
  NATURAL JOIN.  Note that Markus suggested to not specify an explicit
  column to join on...

  The PR suggests the possibility to provide a view that does that
  performs this join but doesn't mandate it and doesn't provide a
  standardized name for it.  Is this desirable?  Should this be
  standardized?  How would this work for combining multiple extensions
  (i.e. Radio + Time Domain).

2. Discovery of ObsCore extensions.

  Converged on using a utype, but there are still multiple suggestions
  for the name (ivo://ivoa.net/std/obsradio#table-1.0
  vs. ivo://ivoa.net/std/ObsCore#obscore-radioExt-1.0) ?

  Should we introduce both table_utype and schema_utype for extensions?

3. t_exp_{min|max|mean}

  These still need a science case in the Appendix.  Can someone
  (Baptiste?) provide one?  Naming is somewhat confusing (name is
  similar to t_exptime in ObsCore, but describing a different
  concept)?  Is the description correct now?

4. s_maximum_angular_scale_{min|max}

  Like the FOV and resolution, the maximum spatial scale is actually
  frequency-dependent.  Should we include min/max values in addition
  to a typical value?

5. f_{min|max}

  These have been dropped in the PR.  How to convert em_{max|min} into
  frequencies has been specified in the standard with a prescribed
  value for the speed of light.  f_resolution has been retained to
  cater for observations with large fractional bandwidth and fixed
  spectral resolution across the band.  Settled?

6. Next steps

  Are we ready for RFC phase?

7. AOB