Detection of pulsar beams deflected by the black hole in Sgr A*: effects of black hole spin

TL;DR

This paper investigates how the spin of the supermassive black hole in Sgr A* affects the deflection of pulsar beams, suggesting pulsar timing could reveal the black hole's spin despite low chances of direct observation.

Contribution

It extends previous models by including black hole spin effects and proposes pulsar timing as a method to estimate the black hole's spin.

Findings

Black hole spin does not significantly affect detection odds.

Pulsar timing can potentially measure the black hole's spin.

Detection chances remain marginal with current telescopes.

Abstract

Some Galactic models predict a significant population of radio pulsars close to the our galactic center. Beams from these pulsars could get strongly deflected by the supermassive black hole (SMBH) believed to reside at the galactic center and reach the Earth. Earlier work assuming a Schwarzschild SMBH gave marginal chances of observing this exotic phenomenon with current telescopes and good chances with future telescopes. Here we calculate the odds of observability for a rotating SMBH. We find that the estimates of observation are not affected by the SMBH spin, but a pulsar timing analysis of deflected pulses might be able to provide an estimate of the spin of the central black hole.