A Radio Astronomy Software tool for creating the Dynamic Spectra for a specified point in the sky from image visibilities in a Measurement Set (MS). The tool offers algorithmic support for beam correction and re-phasing to provide an accurate Jy/beam measure of the specified target. With little overhead, the tool also supports the generation of Dynamic Spectra for multiple targets or off-targets. A larger sample of off-target (randomly sampled within a specified radius of the Phase Center) Dynamic Spectra provide an increasingly accurate variance estimate for the target Dynamic Spectra when used with Inspect_Dynspec.
- Ubuntu 20.04
- Python3.9 virtual environment
- DDFacet installed to virtual environment
- Casa5 installation
git clone https://github.com/saopicc/RIMS.git
pip install ./RIMS
View help:
ms2dynspec --help
Run job:
ms2dynspec --ms <ms location> --data <predicted visibility column> --model <model visibilty column> --srclist <src list location> --rad <radius from which to sample off targets> --noff <number of off targets> --DDFParset <path to parset file for beam correction> --CacheDir <temp directory to write cache> --OutDirName <output directory name>
Notes:
- If you want to creat Dynamic Spectra from residual visibilities, you can specify the model (--model) column and the tool with automatically subtract the model from the data (--data) column.
- Your target in the source list (--srclist) must be within the radius (--rad) specified from Phase Center.
A source file may either be in ECSV format or a simple csv
format of the following structure:
# Example source list
Name ra dec
Deneb 20:41:25.9 +45:16:49
etc 12:00:00.0 +42:00:00
or in fits table format
The output folder should countain the following files/folders:
├── 1541903773.reg
├── Catalog.npy
├── OFF
├── OFF_W
├── TARGET
└── TARGET_W
Where the OFF and OFF_W directories contain the off target and off target weights fits files respectively, and the TARGET and TARGET_W directories contain the target and target weights fits files respectively.
MIT License
Copyright (c) 2017-2025, Cyril Tasse, Alan Loh, Martin Hardcastle, Talon Myburgh, Observatoire de Paris, University of Hertfordshire, Rhodes University