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)
--hdf HDF          Visibility hdf5 file (One minutes worth of visibility data). (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

0.2.0b3 Fix bug in the timensions of the TIME column in the MAIN table. Issue 7.
0.2.0b3 Move to the tart-telescope organization on github..
0.2.0b2 Place all visibilities from HDF5 files into a single measurement set..
0.2.0b1 Add importing of HDF5 files saved from the web app.
0.1.4b4 clean up some bitrot in dask-ms (dealing with chunking objects)
0.1.4b3 Add SIGMA, FLAG, FLAG_CATEGORY to main table (:/)
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.