Parkes observations for project P1196 semester 2023APRS_02

We request observing time at the Parkes telescope for observing three millisecond pulsars (MSPs): J1242-4712, J2101-4800, and J2144-5237. These MSPs were discovered with the GMRT. Spectra, profile evolution with frequency, and the radio polarisation properties of these MSPs are hitherto unexplored. Hence observations with the Parkes UWL receiver will be very valuable in that aspect. We propose radio polarisation study with the Parkes telescope over the large bandwidth of UWL receiver between 0.7 to 4 GHz, to complement our knowledge of spectra and profile evolution with the GMRT observations. Proposed main aims of this proposal are,\n (i) Investigation of profile evolution with frequency\n (ii) Investigation of polarisation angle sweep allowing to constrain the emission geometry.\n (iii) Investigation of spectra for these MSPs from 150 MHz to 4 GHz with Parkes and GMRT observations.\n (iv) Two of the MSPs, J1242-4712, J2101-4800, are spider MSP systems, in a compact orbit with a low mass companion. These systems are extreme southern sources and can be only observed for about 40% of their orbit with the GMRT. The proposed observations with the Parkes UWL will allow us to probe the orbital phase-dependent polarisation and spectral properties of these systems.\n (v) For J2144-5237, a wide pulse profile with multiple profile components is observed. We aim to investigate the steepness of the PA sweep changes as a function of observing frequency for a given profile component as reported from previous investigations.\n We request 32 hrs of observing time at the Parkes to perform this study.