Wide-field VLBI scheduler

This code generates the phase centres for wide-field VLBI correlation. The code can also generate expected simulated data sets and sensitivity maps using realistic EVN primary beams. The code has been tested for the SPARCS (Njeri+in prep.) and COSMOS projects (Radcliffe+in prep.). The final version shall have capabilities to cover an entire area but currently only takes an input catalogue and outputs a VEX format that's suitable format for correlators.

Prerequisites

The code uses python 3.7 and requires the following dependencies that can be installed using pip

• traceback
• logging
• astropy
• numpy

Catalogue pre-processing

Before using this code, it is advisable to do some catalogue pre-processing. In particular:

• Ensure that the prior catalogue can be readable using the astropy Table.read() class. The supported formats are at the bottom of this README and should be used in the table_format input parameter.
• The RA and Dec columns should be in degrees. The code doesn't have the capabilities to convert just yet.

Usage

1. Clone the repository using git clone https://github.com/jradcliffe5/wf_vlbi_scheduler.git.
2. To run the code copy the input file (WFVLBI_inputs.txt) to your current working directory.
3. Edit the input script.
4. Run the script using python <path to repository>/wf_vlbi_scheduler.py or python3 if you have both 2.7 & 3 installed.
5. Check the output is as you expected (see the *.vex file).

Outputs

The code should produce an output vex file format that should be readable by most VLBI correlators. The format is of the $SOURCE format required. It should look similar to the following (otherwise raise an issue).

def ER047001;
    source_name = ER047001;
    ra = 11h56m10.6548s; dec =  62d13'54.7893"; ref_coord_frame = J2000;
enddef;

If you set do_plot=True then you can generate a plot of all the phase centres and their FoVs. The initial source positions along with reduced phase centre locations (as some could be overlapping) are also plotted. An example is shown below.

Supported catalogue formats

Format
ascii
ascii.aastex
ascii.basic
ascii.cds
ascii.commented_header
ascii.csv
ascii.daophot
ascii.ecsv
ascii.fast_basic
ascii.fast_commented_header
ascii.fast_csv
ascii.fast__header
ascii.fast_rdb
ascii.fast_tab
ascii.fixed_width
ascii.fixed_width__header
ascii.fixed_width_two_line
ascii.html
ascii.ipac
ascii.latex
ascii._header
ascii.rdb
ascii.rst
ascii.sextractor
ascii.tab
fits
hdf5
votable
aastex
cds
csv
daophot
html
ipac
latex
rdb