pipeline.hifa.cli.hifa_bandpassflag

pipeline.hifa.cli.hifa_bandpassflag = <pipeline.hifa.cli.hifa_bandpassflag._hifa_bandpassflag object>

hifa_bandpassflag —- Bandpass calibration flagging

This task performs a preliminary phased-up bandpass solution and temporarily applies it, then computes the flagging heuristics by calling hif_correctedampflag which looks for outlier visibility points by statistically examining the scalar difference of the corrected amplitudes minus model amplitudes, and then flags those outliers. The philosophy is that only outlier data points that have remained outliers after calibration will be flagged. Note that the phase of the data is not assessed.

Plots are generated at two points in this workflow: after bandpass calibration but before flagging heuristics are run, and after flagging heuristics have been run and applied. If no points were flagged, the ‘after’ plots are not generated or displayed.

If pipeline mode is ‘getinputs’ then None is returned. Otherwise the results object for the pipeline task is returned.

——— parameter descriptions ———————————————

vis List of input MeasurementSets. Defaults to the list of

MeasurementSets specified in the pipeline context.

Example: vis=[‘ngc5921.ms’]

caltable List of names for the output calibration tables. Defaults

to the standard pipeline naming convention.

Example: caltable=[‘ngc5921.gcal’]

intent A string containing a comma delimited list of intents against

which the selected fields are matched. Set to intent=’’ by default, which means the task will select all data with the BANDPASS intent.

Example: intent=’PHASE’

field The list of field names or field ids for which bandpasses are

computed. Set to field=’’ by default, which means the task will select all fields.

Example: field=’3C279’, field=’3C279,M82’

spw The list of spectral windows and channels for which bandpasses are

computed. Set to spw=’’ by default, which means the task will select all science spectral windows.

Example: spw=’11,13,15,17’

antenna Set of data selection antenna IDs hm_phaseup The pre-bandpass solution phaseup gain heuristics. The options are:

‘snr’: compute solution required to achieve the specified SNR ‘manual’: use manual solution parameters ‘’: skip phaseup

Example: hm_phaseup=’manual’

phaseupsolint The phase correction solution interval in CASA syntax.

Used when hm_phaseup=’manual’ or as a default if the hm_phaseup=’snr’ heuristic computation fails.

Example: phaseupsolint=’300s’

phaseupbw Bandwidth to be used for phaseup. Used when hm_phaseup=’manual’.

Example: phaseupbw=’’ to use entire bandpass

phaseupbw=’500MHz’ to use central 500MHz

phaseupsnr The required SNR for the phaseup solution. Used only if

hm_phaseup=’snr’.

Example: phaseupsnr=10.0

phaseupnsols The minimum number of phaseup gain solutions. Used only if

hm_phaseup=’snr’.

Example: phaseupnsols=4

hm_bandpass The bandpass solution heuristics. The options are:

‘snr’: compute the solution required to achieve the specified SNR ‘smoothed’: simple smoothing heuristics ‘fixed’: use the user defined parameters for all spws

solint Time and channel solution intervals in CASA syntax.

Default is solint=’inf’, which is used when hm_bandpass=’fixed’. If hm_bandpass is set to ‘snr’, then the task will attempt to compute and use an optimal SNR-based solint (and warn if this solint is not good enough). If hm_bandpass is set to ‘smoothed’, the task will use a smoothed solint.

maxchannels The bandpass solution smoothing factor in channels. The

solution interval is bandwidth / 240. Set to 0 for no smoothing. Used if hm_bandpass=’smoothed’.

Example: maxchannels=0

evenbpints Force the per spw frequency solint to be evenly divisible

into the spw bandpass if hm_bandpass=’snr’.

Example: evenbpints=False

bpsnr The required SNR for the bandpass solution. Used only if

hm_bandpass=’snr’.

Example: bpsnr=30.0

minbpsnr The minimum required SNR for the bandpass solution

when strong atmospheric lines exist in Tsys spectra. Used only if hm_bandpass=’snr’.

Example: minbpsnr=10.0

bpnsols The minimum number of bandpass solutions. Used only if

hm_bandpass=’snr’.

combine Data axes to combine for solving. Axes are ‘’, ‘scan’, ‘spw’,

‘field’ or any comma-separated combination.

Example: combine=’scan,field’

refant List of reference antenna names. Defaults to the value(s) stored in the

pipeline context. If undefined in the pipeline context defaults to the CASA reference antenna naming scheme.

Example: refant=’DV06,DV07’

minblperant Minimum number of baselines required per antenna for each solve.

Antennas with fewer baselines are excluded from solutions.

minsnr Solutions below this SNR are rejected solnorm Normalise the bandpass solution antnegsig Lower sigma threshold for identifying outliers as a result of bad

antennas within individual timestamps.

antpossig Upper sigma threshold for identifying outliers as a result of bad

antennas within individual timestamps.

tmantint Threshold for maximum fraction of timestamps that are allowed to

contain outliers.

tmint Initial threshold for maximum fraction of ‘outlier timestamps’

over ‘total timestamps’ that a baseline may be a part of.

tmbl Initial threshold for maximum fraction of ‘bad baselines’ over

‘all baselines’ that an antenna may be a part of.

antblnegsig Lower sigma threshold for identifying outliers as a result of

‘bad baselines’ and/or ‘bad antennas’ within baselines (across all timestamps).

antblpossig Upper sigma threshold for identifying outliers as a result of

‘bad baselines’ and/or ‘bad antennas’ within baselines (across all timestamps).

relaxed_factor Relaxed value to set the threshold scaling factor to under

certain conditions (see task description).

niter Maximum number of times to iterate on evaluation of flagging

heuristics. If an iteration results in no new flags, then subsequent iterations are skipped.

pipelinemode The pipeline operating mode. In ‘automatic’ mode the pipeline

determines the values of all context defined pipeline inputs automatically. In interactive mode the user can set the pipeline context defined parameters manually. In ‘getinputs’ mode the user can check the settings of all pipeline parameters without running the task.

dryrun Run the commands (True) or generate the commands to be run but

do not execute (False).

acceptresults Automatically accept the results of the task into the pipeline context (True)

or reject them (False).

——— examples ———————————————————–

1. run with recommended settings to create bandpass solution with flagging using recommended thresholds:

hifa_bandpassflag()