calwidgetTab.html

Table 1:

CALWIDGET: Calibration widgets

Columns

Key

Data description

Data


Name	Format	Units	Measure	Comments


ANTENNA_ID	Int			Antenna id
FEED_ID	Int			Feed id
SPECTRAL_WINDOW_ID	Int			Spectral window id
TIME	Double	s	EPOCH	Midpoint of time for which this set of parameters is accurate
INTERVAL	Double	s		Interval

NUM_CALLOAD				# of CAL or LOAD N_cl

(CAL)	Double(NUM_CALLOAD)			Noise calibration
(LOAD)	Double(NUM_CALLOAD)			Load temperature
(CALEFF)	float(NUM_RECEPTORS,NUM_CALLOAD)			Calibration widget efficiency/coupling coefficient

Notes: It is indexed directly via CALWIDGET_IDin the SYSCAL table. NUM_RECEPTORS is known through the FEED_ID. Which load is observed at a given time is specified in the STATE table using the item CALLOAD_NUM when REF is TRUE.

ANTENNA_ID: Antenna number, as indexed from ANTENNAn in MAIN
FEED_ID: Feed number, as indexed from FEEDn in the MAIN .
SPECTRAL_WINDOW_ID: Spectral window identifier. A value of -1 indicates the row is valid for all spectral windows. If a specific spectral window has its own feed characteristics these have to be defined separately using a value > 0, to override the global specifications for that specific window.
TIME: Mid point of time interval for which the parameters in the row are valid. The same reference used for the TIME column in the MAIN must be used.
INTERVAL: Time interval. It should be the same as in the FEED table.
NUM_CALLOAD: Number of calibration noise or load available for this feed.
CAL: Noise calibration temperatures (0 if not added) Either CAL or LOAD must be provided but not both simultaneously.
LOAD: Physical temperatures of the load for each calibration widget. Either CAL or LOAD must be provided but not both simultaneously.
CALEFF: Calibration widget efficiency/coupling efficiencies. These efficiencies may not be strictly identical for the different receivers. Additional calibration widget properties to be defined.