Detection of giant pulses from the transitional millisecond pulsar J1227$-$4853

TL;DR

This paper reports the first detection of giant pulses from the transitional millisecond pulsar J1227-4853, revealing extreme variability, phase localization, and clustering behavior, with implications for understanding fast radio bursts.

Contribution

It presents the discovery of giant pulses from a transitional MSP, a phenomenon not previously observed in such systems, and analyzes their temporal and phase characteristics.

Findings

235 GPs detected with widths as narrow as 1.28 microseconds

GP flux densities up to 10,000 times the mean flux

GP arrival times show strong temporal clustering

Abstract

We report the discovery of giant pulse (GP) emission from the transitional millisecond pulsar (tMSP) PSR J1227$-$4853, using 174 hours of single-pulse data from the upgraded Giant Metrewave Radio Telescope (uGMRT). This marks the first detection of GPs from a transitional MSP and adds to the small number of millisecond pulsars known to exhibit such extreme variability. A total of 235 GPs were detected across observations at 550-750 MHz, with widths as narrow as $1.28~\mu s$ and flux densities up to $\sim 10^4$ times the pulsar's mean flux density. The GPs are strongly localized in pulse phase, originating predominantly from the second and third main-pulse components, and are absent in the inter-pulse region. The arrival times of the GPs deviate significantly from Poisson statistics, with the waiting-time distribution well described by a Weibull model having a shape parameter of $k = 0.30$, indicative of strong temporal clustering. During an epoch of enhanced activity, the GP rate increased by nearly two orders of magnitude to $124~\mathrm{hr}^{-1}$, with a corresponding shape parameter of $k = 0.47$. This value is similar to that reported for a burst storm from the repeating fast radio burst FRB 20200120E, suggesting possible phenomenological parallels between GPs from compact binary systems and repeating FRBs.