hif_uvcontsub

hif_uvcontsub(vis=None, field=None, intent=None, spw=None, fitorder=None, parallel=None) → ResultsList[Results][source]

Subtract the continuum from the uv-data using the ranges in cont.dat.

Fits and subtracts the continuum emission for each science target and spw independently using the LSRK frequency ranges from the cont.dat file (produced by hif_findcont). The cont.dat LSRK ranges are translated to the topocentric (TOPO) frame per MS and reported in the WebLog.

Starting in PL2024 the fit order is fitorder=1 by default, but fitorder=0 is used when the LowBW or LowSpread condition was flagged for that spw in hif_findcont (i.e. the selected continuum bandwidth is very small or the selected channels are not well spread across the spw). For any spw listed in cont.dat with no channel ranges specified, the spw is treated as AllContinuum (PL2024+) and no line MS output is produced for that spw.

After this stage the original continuum + line data reside in the DATA column of *_targets.ms, while the continuum-subtracted data are written to the DATA column of the new *_targets_line.ms.

Parameters:

  • vis --

    The list of input MeasurementSets. Defaults to the list of MeasurementSets specified in the <hifa,hifv>_importdata task. '': use all MeasurementSets in the context

    Examples: 'ngc5921.ms', ['ngc5921a.ms', ngc5921b.ms', 'ngc5921c.ms']

  • field --

    The list of field names or field ids for which UV continuum fits are computed. Defaults to all fields.

    Examples: '3C279', '3C279,M82'

  • intent --

    A string containing a comma delimited list of intents against which the selected fields are matched.

    '': Defaults to all data with TARGET intent.

  • spw --

    The list of spectral windows and channels for which uv continuum fits are computed. '', Defaults to all science spectral windows.

    Example: '11,13,15,17'

  • fitorder --

    Polynomial order for the continuum fits per source and spw. Defaults to {} which means fit order 1 for all sources and spws. If an explicit dictionary is given then all unspecified selections still default to 1.

    Example: {'3C279': {'15': 1, '17': 2}, 'M82': {'13': 2}}

  • parallel --

    Process multiple MeasurementSets in parallel using the casampi parallelization framework.

    Options: 'automatic', 'true', 'false', True, False

    Default: None (equivalent to False)

Notes

QA = 1.0 if a continuum fit table is successfully created; 0.0 otherwise.

Returns:

The results object for the pipeline task is returned.

Examples

  1. Subtract continuum for all science targets and spws:

>>> hif_uvcontsub()

  1. Subtract continuum for a subset of fields only:

>>> hif_uvcontsub(field='3C279,M82')

  1. Subtract continuum for selected spws only:

>>> hif_uvcontsub(spw='11,13')

  1. Override the automatic fit order per field and spw:

>>> hif_uvcontsub(fitorder={'3C279': {'15': 1, '17': 2}, 'M82': {'13': 2}})