How to discover Mirror Stars

Non-minimal hidden sectors are an important generic possibility and arise in well motivated theories. Thus a fraction of dark matter could have hidden interactions analogous to Standard Matter (SM) electromagnetism and nuclear physics. This leads to the formation of Mirror Stars: dark-sector analogues of regular stars that shine in dark photons. If the dark and SM photon have a small kinetic mixing, SM matter is captured in Mirror Star cores, giving rise to a dual optical and X-ray signal. This discoverable, robust and highly distinctive signature is a smoking gun of Mirror Stars.