Oral Presentation

Time Variable Radiative Model of SgrA*

Author(s): Hotaka Shiokawa, Sheperd Doeleman, Michael Johnson, Lindy Blackburn

Presenter: Hotaka Shiokawa (Smithsonian Astrophysical Observatory)

Observational time variability of SgrA*, the super massive black hole at the center of Milky Way galaxy, undoubtedly contains valuable information on underlying accretion flow dynamics. In this study, we seek to relate time variability of ultra-high resolution radio observations with the dynamics of background accretion disk using numerical simulations. We run a general relativistic magnetohydrodynamics (GRMHD) simulation of radiatively inefficient accretion flow, and post process the result of the simulation to construct time variable radiation models using fully general relativistic ray-tracing code that takes light traveling time into account. We especially focus on 1.3mm wavelength so that our result can be compared with future Event Horizon Telescope observations of SgrA*. Our simulation pipeline produces data sets expected from the EHT, including complex fourier visibilities, closure phases and closure amplitudes. We will present results from power spectrum density (PSD), periodicity and statistical characterization analyses to study rotation of the accretion flow and turbulence.