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SET SELECTION
CLIC\SET SELECTION mode band subband-list [FREQUENCY freqout]
[/WINDOW fmin fmax [fmin2 fmax2 ...]]
Choose the type of data selection to be done by command TABLE (to create
an output UV table).
- The first argument 'mode' is CONTINUUM or LINE, to prepare single
channel or multiple channel maps.
- The second argument is the sideband to be used: UPPER (or USB), LOWER
(or LSB), AVERAGE (or DSB), AUTO or SSB. DSB may be used in conjunc-
tion with CONTINUUM: in this case, two separate visibility points are
written, one for each sideband. DSB used in conjunction with LINE
means that the side band will be selected to match the desired fre-
quency range (as given in the command TABLE), thus allowing to mix in
the same table data from USB and LSB, if different frequency setups
have been used in different configurations. AUTO will determine for
each narrow input whether the receiver tuning is DSB or SSB and ac-
cordingly select DSB (write a visibility for each sideband) or the
signal sideband if SSB. SSB will write one visibility for the signal
side band (automatically determined). This last two options are use-
ful for continuum only. For LINE, they will just select the matching
side band as does DSB.
- The third argument is a subband list.In CONTINUUM mode, subbands are
averaged, in spectral mode they are combined to produce a single spec-
trum. The subband list is given with the same syntax as in the SET
SUBBAND command, e.g. "n1 to n3" or "n1 to n3 and n5".
Example: SET SELECTION CONTINUUM USB C01 AND C03 AND C05 selects continuum
data, USB, and the subbands C01, C03, and C05.
Arguments "FREQUENCY freqout" are used only for CONTINUUM tables. They
define the frequency (in MHz) used for mapping purposes. U and V (for each
side band in DSB mode) will be scaled to this frequency. This is intended
to combine maps obtained in continuum at slightly different frequencies.
The default for freqout is the actual observing frequency , or the fre-
quency used for previous data if data is appended to a previously existing
table by the TABLE command.
Option /WINDOW is used to avoid spectral lines when producing a continuum
table from spectral correlator data. The first two rest frequencies (in
MHz) give the first frequency window in which data is to be used, the next
two give the second frequency window, etc....
Gildas manager
2011-04-01