Single-pulse observations of the Galactic Center magnetar PSR J1745$-$2900 at 3.1 GHz

TL;DR

This study presents single-pulse radio observations of the Galactic Center magnetar PSR J1745-2900 at 3.1 GHz, revealing stable emission states, mode switching, nulling, and short-term variability over several months.

Contribution

First detailed single-pulse analysis of PSR J1745-2900 at 3.1 GHz, demonstrating mode switching and nulling, indicating similar emission processes to normal pulsars.

Findings

Pulsar was in a stable emission state for 6.8 months.

The pulsar switches between two emission modes approximately every ten minutes.

Nulling and mode changing observed, but no giant pulses or subpulse drifting.

Abstract

We report on single-pulse observations of the Galactic Center magnetar PSR J1745$-$2900 that were made using the Parkes 64-m radio telescope with a central frequency of 3.1 GHz at five observing epochs between 2013 July and August. The shape of the integrated pulse profiles was relatively stable across the five observations, indicating that the pulsar was in a stable state between MJDs 56475 and 56514. This extends the known stable state of this pulsar to 6.8 months. Short term pulse shape variations were also detected. It is shown that this pulsar switches between two emission modes frequently and that the typical duration of each mode is about ten minutes. No giant pulses or subpulse drifting were observed. Apparent nulls in the pulse emission were detected on MJD 56500. Although there are many differences between the radio emission of magnetars and normal radio pulsars, they also share some properties. The detection of mode changing and pulse nulling in PSR J1745$-$2900 suggests that the basic radio emission process for magnetars and normal pulsars is the same.