Prefactor: Preprocessing for Facet Calibration for LOFAR
prefactor is a pipeline to correct for various instrumental and ionospheric effects in both LOFAR HBA and LOFAR LBA observations.
It includes:
- removal of clock offsets between core and remote stations (using clock-TEC separation)
- correction of the polarization alignment between XX and YY
- robust time-independent bandpass correction
- ionospheric RM corrections with RMextract
- removal of the element beam
- advanced flagging and interpolation of bad data
- mitigation of broad-band RFI and bad stations
- direction-independent phase correction of the target, using a global sky model from TGSS ADR or the new Global Sky Model (GSM)
- detailed diagnostics
It will prepare your data to allow you continuing the processing with any direction-dependent calibration software, like Rapthor, factor or killMS.
Note
If you intend to use prefactor for the processing of long baselines (international stations) the user is referred to the LOFAR-VLBI documentation, since the compatibility of both pipelines may be limited to certain version or releases. It is recommended to stick to the instructions therein.
Note: The current version of prefactor does not yet support state-of-the-art calibration of target fields with the LOFAR LBA. An implementation is planned for upcoming releases. Please continue your processing using LiLF.