Numerical light curves for tidal disruption events in black hole-centered Plummer spheres

Abstract

We expand the scope of the analytical TDE model proposed by Lodato, King, and Pringle to encompass non-isolated systems, where the accreting black hole is surrounded by a spherically symmetric mass distribution. Employing the Plummer sphere to model the extended mass, we investigate how the predicted TDE light curves behave across different BH-Plummer sphere mass ratios and Plummer sphere compactness levels. We observe that increasing the mass ratio yields light curves with diminished peaks and prolonged delays, with all regimes displaying a late-time falloff following a t^–5/3 power law scaling. Furthermore, Plummer spheres with intermediate compactness introduce distinctive signatures in light curves, including prolonged shallower decays near peak accretion and a region with decay rates that overshoot from the canonical scaling. Our findings confirm that in the extreme compactness limits, the light curves satisfy theoretical predictions, with all examined scenarios eventually converging to the anticipated power law scaling, albeit very deep in time.