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0.1.5 blcal

Requires:

Synopsis
Calculate a baseline-based calibration solution (gain or bandpass)

Description



Arguments





Inputs

vis

Name of input visibility file

allowed:

string

Default:

caltable

Name of output gain calibration table

allowed:

string

Default:

field

Select field using field id(s) or field name(s)

allowed:

string

Default:

spw

Select spectral window/channels

allowed:

string

Default:

intent

Select observing intent

allowed:

string

Default:

selectdata

Other data selection parameters

allowed:

bool

Default:

True

timerange

Select data based on time range

allowed:

string

Default:

uvrange

Select data within uvrange (default units meters)

allowed:

any

Default:

variant

antenna

Select data based on antenna/baseline

allowed:

string

Default:

scan

Scan number range

allowed:

string

Default:

observation

Select by observation ID(s)

allowed:

any

Default:

variant

msselect

Optional complex data selection (ignore for now)

allowed:

string

Default:

solint

Solution interval

allowed:

any

Default:

variant inf

combine

Data axes which to combine for solve (obs, scan, spw, and/or field)

allowed:

string

Default:

scan

freqdep

Solve for frequency dependent solutions

allowed:

bool

Default:

False

calmode

Type of solution” (’ap’, ’p’, ’a’)

allowed:

string

Default:

ap

solnorm

Normalize average solution amplitudes to 1.0

allowed:

bool

Default:

False

gaintable

Gain calibration table(s) to apply on the fly

allowed:

stringArray

Default:

gainfield

Select a subset of calibrators from gaintable(s)

allowed:

stringArray

Default:

interp

Interpolation mode (in time) to use for each gaintable

allowed:

stringArray

Default:

spwmap

Spectral windows combinations to form for gaintables(s)

allowed:

intArray

Default:

parang

Apply parallactic angle correction

allowed:

bool

Default:

False

Example

 
 
        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  
        intent -- Select observing intent  
                  default: ’’  (no selection by intent)  
                  intent=’*BANDPASS*’  (selects data labelled with  
                                        BANDPASS intent)  
        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=’0~1000klambda’; uvrange from 0-1000 kilo-lambda  
               uvrange=’>4klambda’;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  
        observation -- Observation ID(s).  
                       default: ’’ = all  
                       example: ’0~2,4’  
        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=’1min’; 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 obs, field, and spw boundaries,  
                        but may extend over multiple scans (per obs, field, and spw) up  
                        to solint.  
              Options: ’’,’obs’,’scan’,’spw’,field’, or any comma-separated  
                        combination in a single string  
              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;  
               ’nearest’ ==> nearest (on sky) available field in table  
               otherwise, same syntax as field  
               example: gainfield=’0~3’  
                        gainfield=[’0~3’,’4~6’]  
        interp -- Interpolation type (in time[,freq]) to use for each gaintable.  
                 When frequency interpolation is relevant (B, Df, Xf),  
                 separate time-dependent and freq-dependent interp  
                 types with a comma (freq _after_ the comma).  
                 Specifications for frequency are ignored when the  
                 calibration table has no channel-dependence.  
                 Time-dependent interp options ending in ’PD’ enable a  
                 "phase delay" correction per spw for non-channel-dependent  
                 calibration types.  
                 For multi-obsId datasets, ’perobs’ can be appended to  
                 the time-dependent interpolation specification to  
                 enforce obsId boundaries when interpolating in time.  
                 default: ’’ --> ’linear,linear’ for all gaintable(s)  
                 example: interp=’nearest’   (in time, freq-dep will be  
                                              linear, if relevant)  
                          interp=’linear,cubic’  (linear in time, cubic  
                                                  in freq)  
                          interp=’linearperobs,spline’ (linear in time  
                                                        per obsId,  
                                                        spline in freq)  
                          interp=’,spline’  (spline in freq; linear in  
                                             time by default)  
                          interp=[’nearest,spline’,’linear’]  (for multiple gaintables)  
                 Options: Time: ’nearest’, ’linear’  
                          Freq: ’nearest’, ’linear’, ’cubic’, ’spline’  
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]]  
        parang -- If True, apply the parallactic angle correction (required  
               for polarization calibration)  
               default: False  
 


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