A survey for radio pulsars and transients in the 10 pc region around Sgr A*

TL;DR

This survey used the Effelsberg telescope to search for pulsars and transients near Sgr A*, employing advanced techniques but found no new pulsars, highlighting the need for next-generation instruments for better sensitivity.

Contribution

The paper presents a comprehensive survey of the Galactic Centre region with improved search techniques, demonstrating current limitations and the potential of future radio interferometers.

Findings

No new pulsars detected besides known magnetar

Identified a faint single pulse candidate

Survey sensitivity limited to millisecond pulsars

Abstract

Here we report on a new survey for pulsars and transients in the 10 pc region around Sgr A* using the Effelsberg radio telescope at frequencies between 4 to 8 GHz. Our calibrated full-Stokes data were searched for pulsars and transients using PulsarX, TransientX and PRESTO. Polarisation information is used in the scoring of the candidates. Our periodicity acceleration and jerk searches allowed us to maintain good sensitivity towards binary pulsars in $\gtrsim$ 10-hr orbits. In addition we performed a dedicated search in linear polarisation for slow transients. While our searches yielded no new discovery beyond the redetection of the magnetar SGR J1745-2900, we report on a faint single pulse candidate in addition to several weak periodicity search candidates. After thoroughly assessing our survey's sensitivity, we determined that it is still not sensitive to a population of millisecond pulsars. Next generation radio interferometers can overcome the limitations of traditional single-dish pulsar searches of the Galactic Centre.