Microlensing Black Hole Shadows-II: Constraining Primordial Black Hole Dark Matter using the photon rings of M87 and Sgr A*

Himanshu Verma, Priyanka Sarmah, Joseph Silk +1

The resolution of photon rings of Sgr~A${}^{\ast }$ and M87 is the next milestone of upcoming EHT-like interferometries. We extend the formalism developed in our previous work~\cite{Verma:…