Light echos and coherent autocorrelations in a black hole spacetime
PIRSA ID:
21020052
Series:
Strong Gravity
Event Type:
Seminar
Scientific Area(s):
Strong Gravity
End date:
Speaker(s):
- Paul Chesler, Massachusetts Institute of Technology (MIT) - Department of Physics
Light rays can orbit the photon shell of a black hole many times before escaping to infinity. This means that a distant observer can see a successive series of "echo" images, each separated in time by the photon shell orbital period, and each dimmer than the previous. I will present a study of light echos using coherent autocorrelation functions sourced by fluctuating matter in accretion flows. I will demonstrate that coherent autocorrelation functions are peaked at integer multiples of the photon shell orbital period. Furthermore, I will argue that the power in echos from supermassive black holes is too small to be observed on Earth.
Zoom Link: https://pitp.zoom.us/j/92751681169?pwd=V0hQeUMwaWtTQjQ3UzdxekJiT0lmQT09