instrument_feed

[Bonnarel]

Section 4.4 (September 28th version) reads :

We note that instrument_feed could be changed to instrument_beam to account for the number of beams in the case of a beamforming/PAF receiver.

Question to beam_forming fans : is that OK to keep instrument_feed for the number of beams ?

Or reversely : would instrument_beam be ok for multi feed and beam forming ?

[alle-ira]

Given the discussion on instrumental characterisation (issue #50) instrument_feed may provide too specific information and may puzzle the end user.
First, to properly describe the data content instrument_feed should be given together with another parameter specifying the receiver type (multifeed, PAF/beamforming). In fact, reduction and analysis is different for data coming from multifeed or PAF receivers.
Secondly, if a service exposed multifeed observations with the highest-granularity (that is an ObsCore table lists a multifeed observation as multiple rows, say 9) the user would see in the query output a list of 9 rows. In such a case, which value would be displayed for instrument_feed in each row?
Thus, instrument_feed could be replaced/complemented by an appropriate description of the dataset content by means of dataproduct_subtype.