Dissertation Defense
Student: Pedro Naethe Motta
Program: Astronomy
Title: “GRMHD simulations of X-ray binaries in the hard state”
Advisor: Prof. Dr. Rodrigo Nemmen - IAG/USP
Judging Committee
Chair: Prof. Dr. Rodrigo Nemmen da Silva - IAG/USP – IAG/USP - on videoconference
Members:
- Prof. Dr. Reinaldo Santos de Lima – IAG/USP – on videoconference
- Prof. Dr. Adam Ingram – Newcastle University – on videoconference
- Prof. Dr. Alexander Tchekovskoy – Northwestern University – on videoconference
Black hole X-ray binaries (XRBs) serve as essential astrophysical laboratories for investigating the physics of the accretion flows and black holes. These systems, composed of a black hole and a companion star, exhibit a variety of spectral states, offering a unique opportunity to study the accretion dynamics on shorter timescales when compared to supermassive black holes (SMBHs). In this work, we address the challenge of capturing the radiation processes within XRBs by presenting an implementation of a radiation prescription, which offers a lower computational cost compared to traditional radiative transfer codes, within the GPU-accelerated code \code{H-AMR}. Our approach incorporates a radiative solution that accounts for bremsstrahlung, synchrotron radiation, comptonized synchrotron, and coulomb collisions. Through extensive testing, we validate the functionality of our methodology. Our implementation provides a low-cost tool for investigating the properties and dynamics of black hole accretion flows in XRBs.
Keywords: Numerical Simulations, Black hole physics, Accretion disks, GRMHD, High energy astrophysics