Blcal
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Help on blcal task:
Calculate a baseline-based calibration solution (gain or bandpass)
This task determines a baseline by baseline gain (time) or bandpass (freq)
for all baseline pairs in the data set. For the usual antenna-based calibration
of interferometric data, this task gaincal is recommended, even with only one
to three baselines. For arrays with closure errors, use blcal
Keyword arguments:
vis -- Name of input visibility file
default: none; example: vis='ngc5921.ms'
caltable -- Name of output Gain calibration table
default: none; example: caltable='ngc5921.gcal'
--- Data Selection (see help par.selectdata for more detailed information)
field -- Select field using field id(s) or field name(s).
[run listobs to obtain the list id's or names]
default: ''=all fields
If field string is a non-negative integer, it is assumed a field index
otherwise, it is assumed a field name
field='0~2'; field ids 0,1,2
field='0,4,5~7'; field ids 0,4,5,6,7
field='3C286,3C295'; field named 3C286 adn 3C295
field = '3,4C*'; field id 3, all names starting with 4C
spw -- Select spectral window/channels
default: ''=all spectral windows and channels
spw='0~2,4'; spectral windows 0,1,2,4 (all channels)
spw='<2'; spectral windows less than 2 (i.e. 0,1)
spw='0:5~61'; spw 0, channels 5 to 61
spw='0,10,3:3~45'; spw 0,10 all channels, spw 3, channels 3 to 45.
spw='0~2:2~6'; spw 0,1,2 with channels 2 through 6 in each.
spw='0:0~10;15~60'; spectral window 0 with channels 0-10,15-60
spw='0:0~10,1:20~30,2:1;2;3'; spw 0, channels 0-10,
spw 1, channels 20-30, and spw 2, channels, 1,2 and 3
selectdata -- Other data selection parameters
default: True
timerange -- Select data based on time range:
default = '' (all); examples,
timerange = 'YYYY/MM/DD/hh:mm:ss~YYYY/MM/DD/hh:mm:ss'
Note: if YYYY/MM/DD is missing dat defaults to first day in data set
timerange='09:14:0~09:54:0' picks 40 min on first day
timerange= '25:00:00~27:30:00' picks 1 hr to 3 hr 30min on next day
timerange='09:44:00' data within one integration of time
timerange='>10:24:00' data after this time
uvrange -- Select data within uvrange (default units kilo-lambda)
default: '' (all); example:
uvrange='0~1000kl'; uvrange from 0-1000 kilo-lamgda
uvrange='>4kl';uvranges greater than 4 kilo lambda
uvrange='0~1000km'; uvrange in kilometers
antenna -- Select data based on antenna/baseline
default: '' (all)
If antenna string is a non-negative integer, it is assumed an antenna index
otherwise, it is assumed as an antenna name
antenna='5&6'; baseline between antenna index 5 and index 6.
antenna='VA05&VA06'; baseline between VLA antenna 5 and 6.
antenna='5&6;7&8'; baseline 5-6 and 7-8
antenna='5'; all baselines with antenna 5
antenna='5,6,10'; all baselines with antennas 5 and 6
scan -- Scan number range - New, under developement
msselect -- Optional complex data selection (ignore for now)
solint -- Solution interval (units optional)
default: 'inf' (~infinite, up to boundaries controlled by combine);
Options: 'inf' (~infinite), 'int' (per integration), any float
or integer value with or without units
examples: solint='1m'; solint='60s', solint=60 --> 1 minute
solint='0s'; solint=0; solint='int' --> per integration
solint-'-1s'; solint='inf' --> ~infinite, up to boundaries
enforced by combine
combine -- Data axes to combine for solving
default: 'scan' --> solutions will break at field and spw boundaries,
but may extend over multiple scans (per field and spw) up
to solint.
Options: '','scan','spw',field', or any comma-separated combination
example: combine='scan,spw' --> extend solutions over scan boundaries
(up to the solint), and combine spws for solving
freqdep -- Solve for frequency dependent solutions
default: False (gain; True=bandpass); example: freqdep=True
calmode -- Type of solution
default: 'ap' (amp and phase); example: calmode='p'
Options: 'p','a','ap'
solnorm -- Normalize solutions. For freqdep=F, this is a global (per-spw)
normalization of amplitudes (only). For freqdep=T, each baseline
solution spectrum is separately normalized by its (complex) mean.
default: False (no normalization)
gaintable -- Gain calibration table(s) to apply
default: '' (none);
examples: gaintable='ngc5921.gcal'
gaintable=['ngc5921.ampcal','ngc5921.phcal']
gainfield -- Select a subset of calibrators from gaintable(s)
default:'' ==> all sources in table;
same syntax as field
example: gainfield='0~3'
but may extend over multiple scans (per field and spw) up
to solint.
Options: '','scan','spw',field', or any comma-separated combination
example: combine='scan,spw' --> extend solutions over scan boundaries
(up to the solint), and combine spws for solving
freqdep -- Solve for frequency dependent solutions
default: False (gain; True=bandpass); example: freqdep=True
calmode -- Type of solution
default: 'ap' (amp and phase); example: calmode='p'
Options: 'p','a','ap'
solnorm -- Normalize solutions. For freqdep=F, this is a global (per-spw)
normalization of amplitudes (only). For freqdep=T, each baseline
solution spectrum is separately normalized by its (complex) mean.
default: False (no normalization)
gaintable -- Gain calibration table(s) to apply
default: '' (none);
examples: gaintable='ngc5921.gcal'
gaintable=['ngc5921.ampcal','ngc5921.phcal']
gainfield -- Select a subset of calibrators from gaintable(s)
default:'' ==> all sources in table;
same syntax as field
example: gainfield='0~3'
gainfield=['0~3','4~6']
interp -- Interpolation mode (in time) to use for each gaintable
default: '' --> 'linear' for all gaintable(s)
example: interp='nearest'
interp=['nearest','linear']
Options: 'nearest', 'linear', 'aipslin'
spwmap -- Spectral windows combinations to form for gaintable(s)
default: [] (apply solutions from each spw to that spw only)
Example: spwmap=[0,0,1,1] means apply the caltable solutions
from spw = 0 to the spw 0,1 and spw 1 to spw 2,3.
spwmap=[[0,0,1,1],[0,1,0,1]]
gaincurve -- Apply internal VLA antenna gain curve correction (True/False)
default: False;
Use gaincurve=True ONLY for VLA data
opacity -- Opacity correction to apply (nepers)
default: 0.0 (no opacity correction)
example: opacity=0.051
Typical VLA values are: 5 GHz - 0.013, 8 GHz - 0.013
15 GHz - 0.016, 23 GHz - 0.051, 43 GHz - 0.07
parang -- If True, apply the parallactic angle correction (required
for polarization calibration)
default: False
