Bandpass
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Help for bandpass:
Calculates a bandpass calibration solution
Determines the amplitude and phase as a function of frequency for
each spectral window containing more than one channel. Strong sources
(or many observations of moderately strong sources) are needed to obtain
accurate bandpass functions. The two solution choices are: Individual
antenna/based channel solutions 'B'; and a polynomial fit over the channels
'BPOLY'. The 'B' solutions can determined at any specified time interval, and
is recommended if each channel has good signal-to-noise. Other, 'BPOLY' is
recommended.
Keyword arguments:
vis -- Name of input visibility file
default: none; example: vis='ngc5921.ms'
caltable -- Name of output bandpass calibration table
default: none; example: caltable='ngc5921.bcal'
--- 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
NOTE: ';' to separate channel selections
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 meters)
default: '' (all); example:
uvrange='0~1000kl'; uvrange from 0-1000 kilo-lamgda
uvrange='>4kl';uvranges greater than 4 kilo-lambda
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, 6 and 10
scan -- Select data based on scan number - New, under developement
default: '' (all); example: scan='>3'
msselect -- Optional complex data selection (ignore for now)
--- Solution parameters
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
refant -- Reference antenna name (string)
default: '' (no reference antenna)
example: refant='13' (antenna with index 13)
refant='VA04' (VLA antenna #4)
Use 'go listobs' for antenna listing
minblperant -- Minimum number of baselines required per antenna for each solve
Antennas with fewer baaselines are excluded from solutions. Amplitude
solutions with fewer than 4 baselines, and phase solutions with fewer
than 3 baselines are only trivially constrained, and are no better
than baseline-based solutions.
default: 4
example: minblperant=10 => Antennas participating on 10 or more
baselines are included in the solve
solnorm -- Normalize bandpass amplitudes and phase for each
spw, pol, ant, and timestamp
default: False (no normalization)
bandtype -- Type of bandpass solution (B or BPOLY)
default: 'B'; example: bandtype='BPOLY'
'B' does a channel by channel solution for each
specified spw.
'BPOLY' is somewhat experimental. It will fit an
nth order polynomial for the amplitude and phase
as a function of frequency. Only one fit is made
for all specified spw, and edge channels should be
omitted.
Use taskname=plotcal in order to compare the results from
B and BPOLY.
fillgaps -- Fill flagged solution channels by interpolation
default: 0 (don't interpolate)
example: fillgaps=3 (interpolate gaps 3 channels wide and narrower)
degamp -- Polynomial degree for BPOLY amplitude solution
default: 3; example: degamp=2
degphase -- Polynomial degree for BPOLY phase solution
default: 3; example: degphase=2
visnorm -- Normalize data prior to BPOLY solution
default: False; example: visnorm=True
maskcenter -- Number of channels to avoid in center of each band
default: 0; example: maskcenter=5 (BPOLY only)
maskedge -- Fraction of channels to avoid at each band edge (in %)
default: 5; example: maskedge=3 (BPOLY only)
append -- Append solutions to the (existing) table
default: False; example: append=True
--- Other calibrations to apply on the fly before determining bandpass solution
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]]
append -- Append solutions to the (existing) table
default: False; example: append=True
--- Other calibrations to apply on the fly before determining bandpass solution
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
