tart2ms 0.1.4b2

Convert TART observation data to Measurement Sets

tart2ms

Convert data from a TART radio telescope to measurement set format. This module relies on the excellent dask-ms module as a helper to create the measurement sets. This packate requires python-casacore to be installed on your system

Install

sudo aptitude install python3-casacore
sudo pip3 install tart2ms

Examples

Download data from the TART in real time via the RESTful API (defaults to using the API at https://tart.elec.ac.nz/signal):

tart2ms --ms data.ms

To convert a previously downloads JSON file to a measurement set (MS):

tart2ms --json data.json --ms data.ms

To synthesize (using wsclean) the image from the measurement set:

wsclean -name test -size 1280 1280 -scale 0.0275 -niter 0 data.ms

This will create an image called test-image.fits. You will need to install wsclean on your system.

Usage

usage: tart2ms [-h] [--json JSON] [--ms MS] [--api API] [--catalog CATALOG]
            [--vis VIS] [--pol2]

Generate measurement set from a JSON file from the TART radio telescope.

optional arguments:
-h, --help         show this help message and exit
--json JSON        Snapshot observation JSON file (visiblities, positions
                    and more). (default: None)
--ms MS            Output MS table name. (default: tart.ms)
--api API          Telescope API server URL. (default:
                    https://tart.elec.ac.nz/signal)
--catalog CATALOG  Catalog API URL. (default:
                    https://tart.elec.ac.nz/catalog)
--vis VIS          Use a local JSON file containing the visibilities for
                    visibility data (default: None)
--pol2             Fake a second polarization. Some pipelines choke if there
                    is only one. (default: False)

Credits

Thanks to Simon Perkins and Oleg Smirnov for help in interpreting the measurement set documentation.

TODO

Changelog

• 0.1.4b1 Add RESOLUTION and EFFECTIVE_BW to the SPECTRAL_WINDOW
• 0.1.3b1 Sort out the timestamps correctly, added a handy function for converting to epoch time.
• 0.1.2 Correct pointing direction of the array (in J2000).
• 0.1.1 Added -pol2 switch to generate a second polarization.
• 0.1.0 first functioning release.