Discovery of Three Pulsars from a Galactic Center Pulsar Population

TL;DR

This paper reports the discovery of three pulsars near the Galactic center, suggesting a large, previously undetected neutron star population influenced by scattering effects at radio frequencies.

Contribution

The discovery of three new pulsars near the Galactic center provides evidence for a substantial neutron star population in that region, highlighting the impact of scattering on pulsar detection.

Findings

Three pulsars discovered near the Galactic center.

One pulsar has a very young age (~13 kyr) and high magnetic field.

Detected pulsars have long periods and high dispersion measures.

Abstract

We report the discovery of three pulsars whose large dispersion measures and angular proximity to \sgr indicate the existence of a Galactic center population of neutron stars. The relatively long periods (0.98 to 1.48 s) most likely reflect strong selection against short-period pulsars from radio-wave scattering at the observation frequency of 2 GHz used in our survey with the Green Bank Telescope. One object (PSR J1746-2850I) has a characteristic spindown age of only 13 kyr along with a high surface magnetic field $\sim 4\times 10^{13}$ G. It and a second object found in the same telescope pointing, PSR J1746-2850II (which has the highest known dispersion measure among pulsars), may have originated from recent star formation in the Arches or Quintuplet clusters given their angular locations. Along with a third object, PSR J1745-2910, and two similar high-dispersion, long-period pulsars reported by Johnston et al. (2006), the five objects found so far are 10 to 15 arc min from \sgr, consistent with there being a large pulsar population in the Galactic center, most of whose members are undetectable in relatively low-frequency surveys because of pulse broadening from the same scattering volume that angularly broadens \sgr and OH/IR masers.