Images and Spectral Properties of Two Component Advective Flows Around Black Holes: Effects of Photon Bending

TL;DR

This paper models photon trajectories and images of two-component advective flows around Schwarzschild black holes, incorporating relativistic effects to predict spectra and images, highlighting the influence of gravitational bending.

Contribution

It introduces a Monte-Carlo simulation approach that accounts for photon bending and relativistic effects in modeling black hole accretion flow images and spectra.

Findings

Photon bending affects spectral shape.

Spectra and images vary with accretion rate and inclination.

Relativistic effects are significant in modeling black hole surroundings.

Abstract

Two component advective flow (TCAF) successfully explains spectral and timing properties of black hole candidates. We study the nature of photon trajectories in the vicinity of a Schwarzschild black hole and incorporate this in predicting images of TCAF with a black hole at the Centre. We also compute the emitted spectra. We employ a Monte-Carlo simulation technique to achieve our goal. For accurate prediction of the image and the spectra, null trajectories are generated without constraining the motion to any specific plane. Red shift, bolometric flux and corresponding temperature have been calculated with appropriate relativistic consideration. The centrifugal barrier dominated boundary layer or CENBOL near the inner region of the disk which acts as the Compton cloud is appropriately modelled as a thick accretion disk in Schwarzschild geometry for the purpose of imaging and computing spectra. The variations of spectra and image with physical parameters such as the accretion rate ($\dot{m}_d$) and inclination angle are presented. We show that the gravitational bending effects of photons do change the spectral shape to some extent.