154.13 Modeling the spatial distribution of fragments formed from tidally disrupted stars (Eden Girma)

Date & Time

Jan 4th at 5:30 PM until 6:30 PM




Rating ( votes)

Author(s): Eden Girma1, James Guillochon2

Institution(s): 1. Harvard College, 2. Harvard-Smithsonian Center for Astrophysics

Contributing team(s): Banneker Institute

Roughly once every 104 years, a star passes close enough to the supermassive black hole Sgr A* at the center of the Milky Way to be pulled apart by the black holes tidal forces. The star is then spaghettified into a long stream of mass, with approximately one half being bound to Sgr A* and the other half unbound. Hydrodynamical simulations of this process have revealed that within this stream, the local self-gravity dominates the tidal field of Sgr A*. This residual self-gravity allows for planetary-mass fragments to form along the stream that are then shot out into the galaxy at velocities determined by a spread of binding energies. We develop a Monte Carlo code in Python that models and plots the evolving position of these fragments for a variety of initial conditions that are likely realized in nature. This code utilizes an n-body integrator to differentially solve for the position, velocity, and acceleration of each fragment at every time step. We find that the while the most unbound fragments seem to escape the galaxy entirely, there could potentially be fragments travelling within a few hundred parsecs of our solar system.