chimera

Create wideband TOAs from CHIME pulsar observations (fold mode data). CHIMERA stands for The CHIME Reduction Algorithm.

Usage

$ chimerawb [-h] -i INPUT_DIR [-m METAFILE] -o OUTPUT_DIR -c CONFIG [-r] [--skip_pzap] [--skip_toagen] [-C]

Option	Description
-h, --help	Show a help message and exit
-i INPUT_DIR, --input_dir INPUT_DIR	Directory where input archives are stored.
-m METAFILE, --metafile METAFILE	If given, only process the input files included in METAFILE.
-o OUTPUT_DIR, --output_dir OUTPUT_DIR	Directory where output files will be stored.
-c CONFIG, --config CONFIG	Configuration file (JSON format).
-r, --reprocess	Reprocess files regardless of existing output files.
--skip_pzap	Skip post-scrunch RFI zapping step.
--skip_toagen	Skip TOA generation.
-C, --clean	Remove intermediate files.

Summary

This pipeline takes CHIME fold mode Timer archives as input and produces wide-band TOAs. The processing steps are as follows:

• If the input metafile is given, only the files listed there will be processed. Otherwise, all files present in the input dir will be processed.
• For each input data file:
  • try
    • Convert coherence mode data to Stokes mode.
    • Run RFI excision
    • Convert from Timer to PSRFITS format
    • Scrunch in Frequency and Time, Update DM (Based on the config file)
    • if not --skip_pzap and zap_chans are given in config file
      • Remove bad channels (Defined in the config file)
  • If any of the above processing steps are unsuccessful, skip that file and proceed.
• if not --skip_toagen and the template is given in the config file
  • Create TOA file from successfully processed data files. (Skip files if TOA generation fails.)
  • Validate TOA file.

Dependencies

• PSRCHIVE
• PulsePortraiture
• PINT
• astropy
• loguru

Installation

1. Install astropy, loguru and PINT

   $ pip install astropy loguru pint-pulsar

2. Install psrchive (See https://psrchive.sourceforge.net/download.shtml for instructions)

3. Install PulsePortraiture

   $ pip install git+https://github.com/pennucci/PulsePortraiture.git

4. Install chimera

   $ pip install git+https://github.com/abhisrkckl/chimera.git