Comparison of different Tidal Disruption Event light curve models with TiDE, a new modular open source code

TL;DR

This paper introduces TiDE, a modular open-source code for modeling TDE light curves, compares its models with hydrodynamic simulations, and applies it to observed data to estimate black hole parameters.

Contribution

The paper presents TiDE, a new semi-analytic, object-oriented software for TDE light curve modeling, and compares its results with hydrodynamic simulations and existing codes.

Findings

TiDE models agree well with hydrodynamic simulations for full disruptions.

Parameter estimates for AT2019qiz are generally consistent with previous results.

Discrepancies in black hole mass and efficiency highlight model sensitivities.

Abstract

A tidal disruption event (TDE) occurs when a supermassive black hole disrupts a nearby passing star by tidal forces. The subsequent fallback accretion of the stellar debris results in a luminous transient outburst. Modeling the light curve of such an event may reveal important information, for example the mass of the central black hole. This paper presents the TiDE software based on semi-analytic modeling of TDEs. This object-oriented code contains different models for the accretion rate and the fallback timescale $t_{\rm min}$. We compare the resulting accretion rates to each other and with hydrodynamically simulated ones and find convincing agreement for full disruptions. We present a set of parameters estimated with TiDE for the well-observed TDE candidate AT2019qiz, and compare our results with those given by the MOSFiT code. Most of the parameters are in reasonable agreement, except for the mass and the radiative efficiency of the black hole, both of which depend heavily on the adopted fallback accretion rate.