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Basic Information on passmake
Task: passmake
Purpose: Create passband calibration set
Categories: calibration
PASSMAKE is a MIRIAD task that makes a baseline based passband
calibration dataset, to be used by PASSFIT and CALAPPLY.
Key: vis
The passband calibrator visibility dataset. Only one input
dataset allowed. This is normally an observation of a passband
calibrator (strong continuum source) observed in the same narrow-band
correlator mode as the science source; alternatively, it may be a
passband calibrator observed in the broad-band mode (correlator
mode 4, 40 MHz) provided the frequencies observed in broad-band
mode include the frequencies observed in the narrow-band observed
for the science source.
No default.
Key: select
This keyword selects the subset of the visibility data to be
processed. There are a number of subcommands, which may be
abbreviated. Each may be prefixed with a plus or minus sign to
indicate using or discarding the selected data. Many subcommands
can be given (separate them by commas).
Examples:
'select=time(03OCT30:05:42:08,03OCT30:05:43:09),ant(7)(2)'
'select=-auto,-ant(7,8)'
'select=-ant(7,8),vis(1,15),vis(31,45),vis(301,1000)'
'select=-ant(7,8),-ant(1)(4,6),-ant(2)(4,5,6),-ant(3)(4,5),-ant(4)(5,6),-ant(5)(
See also documentation for subroutine selprobe(), which may very well differ
slightly from this document.
Subcommands include:
time(t1,t2)
Select data between times t1 and t2 (UT). Times are in the format:
yymmmdd.fff
or
yymmmdd:hh:mm:ss.s
Various abbreviations are possible. If no date part is given, then
the time matchs all data (regardless of its date) for the given
time of day. e.g. time(03OCT30:05:41:08,03OCT30:05:43:09)
antennae(a1,a2,...)(b1,b2...)
Select all baselines pairs formed between first and second list of
antennas. The second list is optional and defaults to all antennas.
uvrange(uvmin,uvmax)
Select visibilities with uv radius between uvmin and uvmax (in kilo
wavelenghts). If only one value is given, uvmin is taken as zero.
uvnrange(uvmin,uvmax)
Select visibilities with uv radius between uvmin and uvmax (in
nanoseconds). If only one value is given, uvmin is taken as zero.
visibility(n1,n2)
Select visibilities numbered n1 to n2 inclusive.
increment(inc)
Select every inc'th visibility.
ra(r1,r2)
Select visibilities whose RA is in the range r1 to r2. RAs are given
in the format
hh:mm:ss
or
hh.hhh
Various abbreviations are possible.
dec(d1,d2)
Select visibilites whose DEC is in the range d1 to d2. Declinations
are given in the format
dd:mm:ss
or
dd.ddd
Various abbreviations are possible.
ha(h1,h2)
Selects on hour angle (values in decimal hours or hh:mm:ss)
lst(lst1,lst2)
Selects on LST (values in decimal hours or hh:mm:ss)
elevation(el1,el2)
Selects on elevation (values in degrees)
dra(p1,p2)
Select visibilities for which the RA of the pointing center is offset
from the main pointing center by between p1 and p2 arcseconds.
ddec(p1,p2)
Select visibilities for which the DEC of the pointing center is offset
from the main pointing center by between p1 and p2 arcseconds.
dazim(p1,p2)
Select visibilities for which the DAZIM offset is between p1 and p2 arcseconds.
delev(p1,p2)
Select visibilities for which the DELEV offset is between p1 and p2 arcseconds.
pointing(p1,p2)
Select visibilities with the rms pointing error in the range p1 to p2
arcseconds. If only one number is given, p1 is taken as 0.
polarization(p1,p2,p3,...)
Select visibilities on the basis of their polarization/Stokes parameter.
p1,p2,p3,... can be selected from "i,q,u,v,xx,yy,xy,yx,rr,ll,rl,lr"
Conversion between polarizations Stokes parameters (e.g. convert
linears to Stokes) is not performed by this mechanism (see keyword stokes).
source(SRCNAM1,SRCNAM2,...)
Select correlations from the particular source. Several sources
can be given. An asterisk in the source name is treated as a
wildcard. Note that the sourcename match is done IGNORING CASE.
purpose(LIST[,option])
Select based on the intent/purpose of the observation. Introduced in CARMA,
where the letters B (bandpass), F (fluxcal), G (gaincal), P (polarization),
S (science) and O (other) are used.
Current options are EXACT and any match.
seeing(r1,r2)
Select on seeing monitor rms path length (in microns). The UV variable used
is smonrms for ATCA, rmspath for CARMA
frequency(f1,f2)
Select correlations, where the sky frequency of the first correlation
is in the range f1 to f2 (in GHz). If only a single frequency is
given, then correlations are selected if the first correlation
is within 1% of the given frequency. Note this selects the whole
record. This may include several spectral-windows whose frequency
is quite different from the first correlation in the first window.
amplitude(amplo,amphi)
Select any correlation, where the amplitude is between "amplo" and
"amphi". If only one value is given, then "amphi" is assumed to be
infinite.
shadow(d)
Selects data that would be shadowed by an antenna of diameter "d" meters.
If "d" is zero, then the actual diameter of the antennas (if known) is used.
If some data is shadowed, it is advisable to use an antenna diameter value
greater than the physical antenna size (e.g. 20% larger).
bin(b1,b2)
Select visibilities which have pulsar bin numbers in the range
b1 to b2 inclusive. If b2 is omitted, just pulsar bin b1 is
selected.
on(n)
This is used with single dish observations, anbd selects based
whether the "on" variable in the data is on (1) or off (0).
auto
This is used with files that contain a mix of autocorrelations and
crosscorrelations. This selects just the autocorrelation data.
window(w1,w2,...)
Select by spectral window (IF band in AIPS terminology). See
the help on window for more information.
or
The list of subcommands before and after the 'or' are "ored"
together.
Default: all data selected.
Key: gcal
The phase and amplitude gains solution to apply to data, usually
obtained from using calfit on broad-band observations of the passband
calibrator before and after the narrow-band observations; it is not
used,needed? for mode = self.
Default is to apply NO gains solution.
Key: aver
Type of time-averaging to apply to passband data. Choices are ``vector'',
``scalar'' or ``self calibration''. If self-calbration is selected,
the individual digital correlator channels are divided by the wideband
digital correlator channel AT EACH TIME INTERVAL, then vector averaged.
aver=Self-cal overrides user input for 'mode'.
lower sidebands.
Default: vector
Key: mode
Method for normalizing the digital correlator channels relative to the
USB and LSB wide-band digital channels. Choices are ``cross'' and
``self''. Cross mode normalizes the channels relative to the wide-band
data obtained before and after the narrow-band passband observation,
using the gain file specified by gcal. The channel data are divided at
each time interval by the interpolated fit and averaged according to
values of aver. Self mode normalizes the channel data relative to the
wideband digital correlator by dividing the averaged channel data by the
averaged wideband data; the division is done after averaging according
to the value of aver.
Default is ``cross'' if a gcal file is specified.
Default is ``self'' is no gcal file is specified.
Key: pcal
Name for output passband calibration data file. This file may
be used as an input to calapply to calibrate the passband of
a dataset or passfit to interactively fit low order polynomials.
No default.