This repository was developed for use on the MWA telescope by Andrew Williams with contributions from Paul Hancock.
The triggering logic for individual handlers were developed by various project groups - see the __author__ fields in the scripts in the tracet/ directory.
If you use this code to generate observations for your research please cite the description paper Hancock et al, 2019, and Anderson et al, 2021
This repository is made up of the tracet python moudle and the webapp_tracet.
This module contains useful functions such as:
parse_xml.py - parses a variety of xml files and puts all the relivent data into a standard class.
trigger_logic.py - decided if the parsed xml is worth observing with several methods.
triggerservice.py - calls the web service to schedule observations with the MWA and ATCA telescopes.
The full documentation can be found here
A web application that can automatically monitor for VOEvents and trigger observations based on the parameters the user has set. How to install and use the web app is explained in webapp_tracet/README.md.
The MWA observing schedule is stored in a set of database tables on a PostgreSQL server on-site, with start and stop times stored as the number of seconds since the GPS epoch ('GPS seconds'). All observations must start and stop on an integer multiple of eight GPS seconds, so while an observation in progress can be truncated by changing it's stop time, the modulo 8 seconds constraint gives a natural latency of up to 8 seconds. In practice, the Monitor and Control system gives the various components of the telescope time to prepare, by sending their new configuration a few seconds ahead of the start of each observation. This means that a running observation cannot have its stop time changed to a value less than four seconds in the future, and a new observation can't be scheduled to start less than 4 seconds in the future. Including other processing delays, this gives a latency period of 8-16 seconds between the trigger time and the start of a triggered observation.