Radio Observations of a Candidate Redback Millisecond Pulsar: 1FGL J0523.5-2529

TL;DR

This study conducted extensive radio observations of the candidate redback millisecond pulsar 1FGL J0523.5-2529, but found no detectable radio pulsations, emphasizing the challenges in observing such systems and the need for multi-wavelength approaches.

Contribution

The paper provides the first comprehensive radio search for pulsations from J0523.5-2529, highlighting the difficulties in detecting radio emission in redback systems despite extensive orbital coverage.

Findings

No radio pulsations detected despite 34.5 hours of observations.

Radio emission may be suppressed by scattering, eclipses, or intrinsic faintness.

Results underscore the importance of multi-wavelength follow-up for redback pulsars.

Abstract

Redback pulsars are a subclass of millisecond pulsar system with a low-mass non-degenerate companion star being ablated by the pulsar. They are of interest due to the insights they can provide for late-stage pulsar evolution during the recycling process. J0523.5-2529 is one such candidate where redback-like emission has been seen at multiple wavelengths except radio. It is a system with a binary orbit of 16.5 hours and a low-mass non-degenerate companion of approximately 0.8 solar masses. The aim of this work was to conduct follow-up radio observations to search for any exhibited radio pulsar emission from J0523.5-2529. This work employs a periodicity and single burst search across 74 percent of the system's orbital phase using a total of 34.5 hours of observations. Observations were carried out using the Murriyang Telescope at Parkes and the Robert C. Byrd Green Bank Telescope (GBT). Despite extensive orbital phase coverage, no periodic or single-pulse radio emission was detected above a signal-to-noise threshold of 7. A comprehensive search for radio pulsations from J0523.5-2529 using Parkes and GBT yielded no significant emission, likely due to intrinsic faintness, scattering, or eclipses by the companion's outflow. The results demonstrate the elusiveness of the pulsar component in some redback systems and highlight the need for multi-wavelength follow-up and higher-frequency radio observations to constrain the source nature and binary dynamics.