Schwarzschild Barrier

This is an N-body simulation of 50 stars orbiting around a supermassive black hole (SBH). The y-axis is the orbital semi-major axis in milliparsecs. The x-axis is the orbital eccentricity. The stars scatter each other onto different orbits; if they cross the black dashed line, they are captured by the SBH. The red dotted line is the "Schwarzschild Barrier" which "reflects" stars to lower eccentricities, thus keeping them from being captured. One star crosses the barrier, around 3x10^5 years, and is captured. (See Physical Review D, vol. 84, Issue 4, id. 044024, 2011.)