Eclipsing light curves for accretion flows around a rotating black hole and atmospheric effects of the companion star

Understand

We calculate eclipsing light curves for accretion flows around a rotating black hole taking into account the atmospheric effects of the companion star.

• In the cases of no atmospheric effects, the light curves contain the information of the black hole spin because most of the X-ray photons around 1 keV usually come from the blueshifted part of the accretion flow near the black hole shadow, and the size and the position of the black hole shadow depend on the spin.
• In these cases, when most of the emission comes from the vicinity of the event horizon, the light curves become asymmetric at ingress and egress.
• We next investigate the atmospheric absorption and scattering effects of the companion stars.