Research Interests
I am a postdoctoral fellow in the Theoretical Astrophysics Center at the University of California, Berkeley. I was previously a graduate student at the University of Washington, where my PhD advisor was Eric Agol. You can find a copy of my dissertation here.
My work focuses on the observational properties of gas falling into black holes (black hole accretion flows). I have written a public computer code for calculating light trajectories in the vicinity of a spinning black hole (geokerr) as part of a larger code for calculating the appearance of black hole accretion flows. I have used this code to compare sophisticated simulations of the hot, magnetized accreting gas with observations of the Galactic center massive black hole candidate (Sgr A*) from the Event Horizon Telescope. I have also made predictions for future Event Horizon Telescope observations of both Sgr A* and M87, a much larger black hole known for its galaxy-scale jet. This M87 work has recently been featured on a couple of websites:
New
Scientist: Astrophile: A-list black hole gets a face
Astrobites:
Shadow of a black hole
I have also studied the observational properties of tilted black hole accretion disks, which are likely to be very common for low-luminosity stellar mass and supermassive black holes. Finally, I have argued that optical/UV observations of quasars, the brightest persistent sources in the Universe, indicate that they have strongly inhomogeneous accretion disks, much different than what is normally assumed.
Contact
Jason Dexter (jdexter at berkeley.edu)Theoretical Astrophysics Center
Department of Astronomy
University of California at Berkeley
Berkeley, CA 94720-3411