We revisit prior work on the 200 MHz local radio luminosity function (RLF) to produce the most accurate measurement to date. We combine the low-frequency (70 − 230 MHz) Galactic and Extragalactic Murchison Widefield Array (GLEAM) survey with the 6dFGS spectroscopic survey. We build on recent work (Franzen et al., 2021b) by (a) including source previously excluded (‘A-Team’ radio sources and...
The GaLactic and Extragalactic All-sky MWA eXtended(GLEAM-X) survey boasts twice the resolution and up to an order of magnitude higher sensitivity to its predecessor the GLEAM survey. In 2020, observations for GLEAM-X were completed and the first data release was published earlier this year covering 2,000 square degrees down to an RMS noise level of <1.5 mJy/beam. The team is now working on...
It has been an exciting year for the solar science group of the MWA. We have had significant developments on both fronts - developing novel calibration and imaging alogrithms and pipelines, as well as using them to pursure novel science. On the techniques front the sperctro-polarimetric snapshot images from our pipeline now defines the state-of-the-art and achieve polarisation purity on par...
Observations spanning across wavelengths ranging from X-rays, Extreme Ultraviolet, optical and radio bands have demonstrated that copious amounts of nonthermal particles are generated during solar flares. Numerical simulations have also become more and more realistic and for the first time produced nonthermal particle spectra consistent with observations. However most observations of these...
Magnetic reconnection is a well-known process for the acceleration of electrons in the solar corona. When streams of semi-relativistic electrons travel through the hot magnetized coronal plasma along open magnetic field lines, it can result in type-III solar radio bursts by plasma emission mechanism. These radio emissions are among the most widely studied solar phenomenon at meter-wavelength....
Type II solar radio bursts are well known to be predominantly associated with the more energetic and fast coronal mass ejections (CMEs). These CMEs are expected to drive shocks in the coronal medium and play a dominant role in giving rise to energetic particles which are the biggest concern for Space Weather. Type II radio bursts arise from plasma emission mechanisms and occur at fundamental...
Low-frequency radio observations have been expected to serve as a powerful tool for Space Weather observations for decades. This is because (1) radio observations are sensitive to a wide range of Space Weather-related observations ranging from emissions from coronal mass ejections (CMEs) to studies of the solar wind; and (2) the ground-based radio observatories provide high sensitivity data at...
Our current understanding of coronal mass ejections, as well as other solar events in interplanetary space, is well-developed to forecast the effects on Earth. However, it is still insufficient in its ability to predict the evolution of these events with a high degree of accuracy. Considering that a major space weather event could put crucial technologies at risk, predicting the severity of...
Calibrating the MWA as a dual-polarised instrument is notoriously difficult, evidenced by the fact that even our latest beam models and calibration algorithms produce solutions that demonstrably contain frequency-dependent phase errors between the two polarisations. In this talk, I will present an overview of the basic problem using a combination of intuitive and mathematical arguments, and...
Typical radio-interferometer observations are performed assuming the source of radiation to be in the far-field of the instrument, resulting in a Fourier relationship between the observed visibilities in the aperture plane and the sky brightness distribution. When such observations are performed of events in the near-field, radiation with curved wavefronts are correlated with far-field delays...
The MWA, like many radio array telecopes, uses Ethernet packets to route data from the receiver 'frontend' to the MWAX correlator 'backend'. Using a routing feature called Multicast, these data packets can be sent to any backends that request a copy of the datastream. Here, we report on the commensal MWA beamformer system: a collaboration between ICRAR researchers and the Breakthrough Listen...
The Southern-sky MWA Rapid Two-metre (SMART) pulsar survey is an ambitious project, with prospects of discovering hundreds of new pulsars, and will be a valuable prototype for future SKA-Low pulsar surveys. Now that the first ("shallow") stage processing of SMART data is nearing completion, we have started planning for the full survey processing workflow in earnest. I will present our current...
Pulsars are excellent astrophysical laboratories for studying physics under extreme conditions such as ultra-strong gravitational and magnetic fields. Admittedly, after five decades since their discovery, physical processes governing their emission mechanism remain poorly understood. PSR J0026-1955, which was independently discovered by the MWA (McSweeney et al. 2022), exhibits unusual...
