Polarization of Radiation from Accretion Disks around Spinning Black Holes 841 views

The simulation of black hole accretion disks has become particularly relevant with the success of the Event Horizon Telescope in imaging the super massive black hole at the center of M87. With high resolution and broadband imaging of accreting black holes on the horizon, the implementation and testing of codes for modelling the theories surrounding these extreme objects is more important than ever. Building on the foundations of the geokerr code, produced by Dexter & Agol (2009), the IPOLE code, produced by Moscibrodzka & Gammie (2018), and the Athena++ code, created by (Stone et al.,in press), we develop methods for the efficient and accurate calculation and plotting of polarization of light emitted from thin black hole accretion disks. By dually implementing the polarization methods of Dexter (2016) and Moscibrodzka & Gammie (2018), we confirm the polarization basis method of Dexter accurately approximates the more general tensor based approach of Moscibrodzka. Small differences exist between the Dexter and Moscibrodzka methods, but can be explained by bugs in our implementation of general relativity, especially in regards to spinning black holes. We also confirm the Athena++ polarization extensions accurately recreate the results presented in Dexter (2016), and are able to operate at a variety of spins and viewing angles. This thesis is submitted in partial completion of the requirements of the BS Astronomy-Physics Major.

BS (Bachelor of Science)

black hole; simulation; polarization; astronomy; accretion disks

English

2021-05-15