Fast Transients with the Murchison Widefield Array

Abstract

The Murchison Widefield Array (MWA) is a low-frequency interferometer telescope located in the Western Australian outback, operating in the 70 – 300 MHz band, and comprised of 8096 dual-polarisation dipole antennas that are arranged in groups of 16 (tiles), with a maximum baseline out to ~6 km. Even though the array was originally designed and built primarily as an imaging telescope, the eventual development of a voltage capture system (VCS) functionality, whereby unprocessed voltage data can be recorded from all operating tiles opened up opportunities for pulsar and fast transient exploration in the southern skies with this next-generation telescope. Over the past decade, a series of capability enhancements around the VCS and associated software subsystems for post processing (on HPC platforms) has enabled a wide range of pulsar science, provided triggering/shadowing opportunities for GRBs/FRBs, and even facilitated non-astronomical applications involving passive radar or tracking space debris. These efforts have also led to the conception and undertaking of the Southern-sky MWA Rapid Two-metre (SMART) survey – an ambitious project that aims to conduct sensitive searches for pulsars and fast transients in the low-frequency southern skies. With the imminent transition of the array to Phase III by the end of the year, real-time processing and beamforming will replace the data-intensive VCS. I will present an overview of some key technical/science accomplishments in the past years, including new pulsar discoveries flowing on from the SMART project, ongoing efforts to develop a fast-imaging capability (offline processing) to realise large sky surveys for FRBs, and new opportunities now on the horizon for monitoring science in the areas of pulsars and fast transients.