A strongly magnetized pulsar within grasp of the Milky Way's supermassive black hole

TL;DR

This paper reports the discovery and detailed characterization of a young, strongly magnetized pulsar (magnetar) near the Milky Way's supermassive black hole, SgrA*, including its properties, orbit, and potential influence on surrounding molecular clouds.

Contribution

The study provides the first precise localization and characterization of a magnetar close to SgrA*, revealing its properties and likely bound orbit, and suggests its past activity influenced Galactic center phenomena.

Findings

Discovered a young magnetar near SgrA* with high dispersion measure.

Measured the magnetar's spin period and derivative, confirming its youth.

Simulations indicate the magnetar is likely in a bound orbit around SgrA*.

Abstract

The center of our Galaxy hosts a supermassive black hole, Sagittarius (Sgr) A*. Young, massive stars within 0.5 pc of SgrA* are evidence of an episode of intense star formation near the black hole a few Myr ago, which might have left behind a young neutron star traveling deep into SgrA*'s gravitational potential. On 2013 April 25, a short X-ray burst was observed from the direction of the Galactic center. Thanks to a series of observations with the Chandra and the Swift satellites, we pinpoint the associated magnetar at an angular distance of 2.4+/-0.3 arcsec from SgrA*, and refine the source spin period and its derivative (P=3.7635537(2) s and \dot{P} = 6.61(4)x10^{-12} s/s), confirmed by quasi simultaneous radio observations performed with the Green Bank (GBT) and Parkes antennas, which also constrain a Dispersion Measure of DM=1750+/-50 pc cm^{-3}, the highest ever observed for a radio pulsar. We have found that this X-ray source is a young magnetar at ~0.07-2 pc from SgrA*. Simulations of its possible motion around SgrA* show that it is likely (~90% probability) in a bound orbit around the black hole. The radiation front produced by the past activity from the magnetar passing through the molecular clouds surrounding the Galactic center region, might be responsible for a large fraction of the light echoes observed in the Fe fluorescence features.