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: http://www.atnf.csiro.au/computing/software/askapsoft/sdp/docs/current/BETApipelines/BandpassCalibrator.html
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These parameters govern all processing used for the calibrator observation. The requested measurement set is split up by beam and scan, assuming that a given beam points at 1934-638 in the correspondingly-numbered scan.
The MS is then flagged twices: first a dynamic flag is applied (integrating over individual spectra), then a straight amplitude cut is applied to remove any remaining spikes. The dynamic flagging step can also optionally include antenna or baseline flagging.
Then the bandpass table is calculated with cbpcalibrator, which requires MSs for all beams to be given. This is a parallel job, the size of which is configurable through NUM_CPUS_CBPCAL.
| Variable | Default | Parset equivalent | Description |
|---|---|---|---|
| DO_SPLIT_1934 | true | none | Whether to split a given beam/scan from the input 1934 MS |
| DO_FLAG_1934 | true | none | Whether to flag the splitted-out 1934 MS |
| DO_FIND_BANDPASS | true | none | Whether to fit for the bandpass using all 1934-638 MSs |
| MS_BASE_1934 | 1934_beam%b.ms | none | Base name for the 1934 measurement sets after splitting. The wildcard %b will be replaced with the beam number. |
| CHAN_RANGE_1934 | “1-16416” | channel (mssplit (Measurement Splitting/Averaging Utility)) | Channel range for splitting (1-based!). This range also defines the internal variable NUM_CHAN_1934 (which replaces the previously-available parameter NUM_CHAN) |
| FLAG_THRESHOLD_DYNAMIC_1934 | 4.0 | amplitude_flagger.threshold amplitude_flagger.integrateSpectra.threshold (cflag (Flagging Utility)) | Dynamic threshold applied to amplitudes when flagging 1934 data [sigma] |
| FLAG_THRESHOLD_AMPLITUDE_1934 | 0.2 | amplitude_flagger.high (cflag (Flagging Utility)) | Second amplitude threshold applied when flagging 1934 data [hardware units - before calibration] |
| ANTENNA_FLAG_1934 | “” | selection_flagger.<rule>.antenna (cflag (Flagging Utility)) | Allows flagging of antennas or baselines. For example, to flag out the 1-3 baseline, set this to “ak01&&ak03” (with the quote marks). See documentation for further details on format. |
| DIRECTION_1934 | “[19h39m25.036, -63.42.45.63, J2000]” | sources.field1.direction (cbpcalibrator) | Location of 1934-638, formatted for use in cbpcalibrator. |
| TABLE_BANDPASS | calparameters_1934_bp.tab | calibaccess.table (cbpcalibrator and ccalapply (Calibration Applicator)) | Name of the CASA table used for the bandpass calibration parameters. |
| NCYCLES_BANDPASS_CAL | 25 | ncycles (cbpcalibrator) | Number of cycles used in cbpcalibrator. |
| NUM_CPUS_CBPCAL | 400 | none | The number of cpus allocated to the cbpcalibrator job. The job will use all 20 cpus on each node (the memory footprint is small enough to allow this). |