With most physicists and astrophysicists in agreement that black holes do indeed exist, the
focus of astrophysical black hole research has shifted to the detailed properties of these …

This paper investigates the thermodynamic behaviors and optical properties of regular black
holes within pure gravity theories, notable for their absence of singularities. Using both …

The two high-redshift gamma-ray bursts, GRB 080913 at z= 6.7 and GRB 090423 at z= 8.2,
recently detected by Swift appear as intrinsically short, hard GRBs. They could have been …

We consider a subset of the physical processes that determine the spin j≡ a/M of
astrophysical black holes. These include (1) Initial conditions. Recent models suggest that …

Abstract We present XMM-Newton European Photon Imaging Camera (EPIC) observations
of the bright Seyfert 1 galaxy MCG–6-30-15, focusing on the broad Fe K α line at∼ 6 keV …

We interpret the 1.3 mm VLBI observations made by the Event Horizon Telescope of the
black hole in M87. It is proposed that, instead of being a torus of accreting gas, the observed …

We use a ray-tracing technique to compute the observed spectrum of a thin accretion disk
around a Kerr black hole. We include all relativistic effects such as frame-dragging, Doppler …

Evolution characteristics of a Kerr black hole (BH) are investigated by considering the
coexistence of disc accretion with the Blandford–Znajek process (the BZ process) and …

We consider a stationary axisymmetric force-free degenerate magnetosphere of a rotating
Kerr black hole surrounded by a thin, Keplerian, infinitely conducting accretion disk. We …

Recent observations and theoretical work on gamma-ray bursts favor the central engine
model of a Kerr black hole (BH) surrounded by a magnetized neutrino-dominated accretion …