# Does Explosive Nuclear Burning occur in Tidal Disruption Events of White Dwarfs by Intermediate Mass Black Holes ?

## TL;DR

This study uses high-resolution 3D and 1D simulations to explore whether nuclear detonations occur during white dwarf tidal disruptions by intermediate mass black holes, finding no shock-induced detonations at current resolutions.

## Contribution

The paper provides unprecedented high-resolution simulations showing the absence of shock waves and detonations in white dwarf tidal disruption events, challenging previous assumptions.

## Key findings

- Nuclear reactions decrease with higher resolution due to spurious heating.
- No shock wave generation observed in 3D simulations at high resolution.
- Shock waves and potential detonations found in 1D simulations at high resolution.

## Abstract

We investigate nucleosynthesis in tidal disruption events (TDEs) of white dwarfs (WDs) by intermediate mass black holes (IMBHs). We consider various types of WDs with different masses and compositions by means of 3 dimensional (3D) smoothed particle hydrodynamics (SPH) simulations. We model these WDs with different numbers of SPH particles, $N$, from a few $10^4$ to a few $10^7$, in order to check mass resolution convergence, where SPH simulations with $N>10^7$ (or a space resolution of several $10^6$ cm) have unprecedentedly high resolution in this kind of simulations. We find that nuclear reactions become less active with increasing $N$, and that these nuclear reactions are excited by spurious heating due to low resolution. Moreover, we find no shock wave generation. In order to investigate the reason for the absence of a shock wave, we additionally perform 1 dimensional (1D) SPH and mesh-based simulations with a space resolution ranging from $10^4$ to $10^7$ cm, using characteristic flow structure extracted from the 3D SPH simulations. We find shock waves in these 1D high-resolution simulations. One of these shock waves triggers a detonation wave. However, we have to be careful of the fact that, if the shock wave emerged at a bit outer region, it could not trigger the detonation wave due to low density. Note that the 1D initial conditions lack accuracy to precisely determine where a shock wave emerges. We need to perform 3D simulations with $\lesssim 10^6$ cm space resolution in order to conclude that WD TDEs become optical transients powered by radioactive nuclei.