The disturbance of a millisecond pulsar magnetosphere

TL;DR

This paper reports on a sudden, long-lasting change in the pulse profile of a millisecond pulsar, which could impact pulsar timing accuracy and gravitational wave detection.

Contribution

It identifies a new type of pulse profile variation in a millisecond pulsar and discusses its implications for pulsar timing and gravitational wave searches.

Findings

A new emission component appeared suddenly in the pulse profile.

The profile variation decayed over four months and became permanent.

Such variations may explain timing noise in millisecond pulsars.

Abstract

Pulsar timing has enabled some of the strongest tests of fundamental physics. Central to the technique is the assumption that the detected radio pulses can be used to accurately measure the rotation of the pulsar. Here we report on a broad-band variation in the pulse profile of the millisecond pulsar J1643-1224. A new component of emission suddenly appears in the pulse profile, decays over 4 months, and results in a permanently modified pulse shape. Profile variations such as these may be the origin of timing noise observed in other millisecond pulsars. The sensitivity of pulsar-timing observations to gravitational radiation can be increased by accounting for this variability.