The Low-Frequency Square Kilometre Array (SKA-Low) is the next-generation radio telescope which will be built at the Murchison Radio-astronomy Observatory (MRO) in the next decade. The telescope will consist of 512 stations composed of 256 dual-polarised antennas each and will observe at frequencies between 50 and 350 MHz. It will be used to pursue wide variety of science goals including radio transients.
In 2019, two prototype stations of the SKA-Low, the Engineering Development Array 2 (EDA2) and Aperture Array Verification System 2 (AAVS2), were deployed at the MRO and have been regularly collecting data for engineering and science purposes. These stations can be used to form station beams in arbitrary directions in the sky or as standalone low-frequency interferometers capable of forming all-sky images. Long observations (usually exceeding 24 hours) have already been conducted with both stations at several frequencies resulting in thousands of all-sky images. The sensitivity of each individual station allows for detection of relatively bright radio-transients. However, the collected data show that there is a variety of objects which can be found in these images ranging from radio-frequency interference (RFI) emitted or reflected by aircraft or satellites to genuine astrophysical transients (for example extreme scintillation of pulsar emission). Recent low-frequency detections of fast radio-bursts (FRBs) down to 328 MHz by other radio-telescopes open a possibility that very bright low-frequency FRBs could also be detected by such an all-sky imaging system.
In order to identify astrophysical transients amongst large amounts of RFI events and characterise transient objects observed in the all-sky images a robust classification system is required. The goal of this project is to design, development and characterise (for example verify efficiency of astrophysical transients detection) an automatic real-time system for transient detection, classification (machine learning techniques are to be considered) and cross-matching with external catalogues. Depending on candidate’s interests this project offers a variety of avenues as it can evolve towards science oriented goals (such as analysis of the detected transients of astrophysical origin) or engineering goals, such as continuous monitoring of the RFI environment at the MRO, which will be critical for most of the science programs undertaken by the SKA-Low telescope. Furthermore, the RFI reflection events flagged by the algorithm can be used as an input for algorithms identifying, calculating and cataloguing orbital parameters of space debris elements, which is becoming a critical task for the future of the space exploration. Hence, another path for the final stage of the project is to explore the detected transients in collaboration with the group at Curtin Institute of Radio Astronomy working on identification and tracking of space debris elements.
In summary, the first part of the project will provide valuable results which will be explored for specific science and engineering goals related to the SKA-Low telescope in the second part of the project with the main focus depending upon the specific science or engineering interests of the selected candidate.