Parkes observations for project P1136 semester 2021OCTS_01

Fast radio bursts (FRBs) continue to raise more questions than they answer. Of an order of a thousand discovered FRBs, only 20 of them are known to repeat, and their spectro-temporal properties hint at differences with apparently non-repeating bursts. The repeating FRB sources show varying degrees of activity, with two of them emitting repetitions in a periodic cycle. Here we propose to study repetitions in a sample of five repeating FRB sources, ASKAP-discovered FRB20171019A and FRB20190711A, Parkes-discovered FRB20180301A and CHIME-discovered FRB20201124A and FRB20190117A. We request Parkes observations with the UWL to characterize the broadband emission properties of these sources, with the following key goals: to constrain the repetition rate, confirm any periodicity, identify the variation of pulse characteristics over time and frequency, measure the polarimetric properties and provide insight into the emission mechanism. Understanding the diverse polarization properties from these sources could be the key to distinguish repeater sources from the apparent non-repeaters ones. We have discovered several narrowband repetitions from some of these FRB sources with the UWL, demonstrating the instrument's power to identify repeats and place strong constraints on the burst emission mechanism. We will use the unique wide bandwidth observations to test leading models of burst emission for these repeating bursts.