Absorption and scattering of scalar wave from Schwarzschild black hole surrounded by magnetic field

The astronomical observations imply the existence of a strong magnetic field of up to 10(4)-10(8) G near supermassive black holes in the active galactic nuclei and even around stellar mass black holes. Based on the quantum scattering theory, we analyze the Schrodinger-type scalar wave equation of black hole surrounded by a magnetic field and numerically investigate its absorption cross section and scattering cross section in this paper. We find that the absorption cross section oscillates about the geometric optical value in the high frequency regime. Furthermore, the magnetic field makes the absorption cross section weaker in the low frequency regime, and this effect is more obvious on lower frequency band. On the other hand, we find that the magnetic field makes the scattering flux weaker and its width narrower in the forward direction. There also exists the glory phenomenon along the backward direction. At fixed frequency, the glory peak is higher and the glory width becomes narrower due to the magnetic field.