Prospects for Constraining the Yukawa Gravity with Pulsars around Sgr A*

Dong, Yiming

The discovery of radio pulsars (PSRs) around the supermassive black hole (SMBH) in our Galactic Center (GC), Sagittarius A* (Sgr A*) will have significant implications for gravity theory tests. In this paper, we assume that we have detected pulsars around Sgr A* and predict restrictions from such pulsars on parameters of the Yukawa gravity by pulsar timing. Our simulations show that the PSR-SMBH system will shrink the parameter space of the Yukawa gravity when the range of Yukawa interaction varies between 10^{1} – 10^{4} AU and limit the graviton mass to less than 10^{−25} eV, based on timing accuracy of the time of arrivals (TOAs) of pulses σ_{TOA} = 100 μs and 960 TOAs in 20-yr observation.