Radio Detection of the Fermi LAT Blind Search Millisecond Pulsar J1311-3430

TL;DR

This paper reports the first radio detection of a millisecond pulsar found via gamma-ray data, demonstrating its radio emission and providing insights into its beaming and distance, with implications for MSP studies.

Contribution

It presents the first radio detection of PSR J1311-3430 discovered through Fermi LAT gamma-ray blind search, showing it is not radio quiet and expanding understanding of MSP emission.

Findings

Radio pulsations detected at 2 GHz for less than 10% of observations.

Estimated distance of 1.4 kpc based on radio detection.

Gamma-ray efficiency of 30%, typical for LAT-detected MSPs.

Abstract

We report the detection of radio emission from PSR J1311-3430, the first millisecond pulsar discovered in a blind search of Fermi Large Area Telescope (LAT) gamma-ray data. We detected radio pulsations at 2 GHz, visible for <10% of ~4.5-hrs of observations using the Green Bank Telescope (GBT). Observations at 5 GHz with the GBT and at several lower frequencies with Parkes, Nancay, and the Giant Metrewave Radio Telescope resulted in non-detections. We also report the faint detection of a steep spectrum continuum radio source (0.1 mJy at 5 GHz) in interferometric imaging observations with the Jansky Very Large Array. These detections demonstrate that PSR J1311-3430, is not radio quiet and provides additional evidence that the radio beaming fraction of millisecond pulsars is very large. The radio detection yields a distance estimate of 1.4 kpc for the system, yielding a gamma-ray efficiency of 30%, typical of LAT-detected MSPs. We see apparent excess delay in the radio pulsar as the pulsar appears from eclipse and we speculate on possible mechanisms for the non-detections of the pulse at other orbital phases and observing frequencies.