Tidal Disruption Events through the Lens of the Cooling Envelope Model

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Sarin, Nikhil, Metzger, Brian D.
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866929215181422592
author Sarin, Nikhil
Metzger, Brian D.
author_facet Sarin, Nikhil
Metzger, Brian D.
contents The cooling envelope model for tidal disruption events (TDE) postulates that while the stellar debris streams rapidly dissipate their bulk kinetic energy (``circularize"), this does not necessarily imply rapid feeding of the supermassive black hole (SMBH). The bound material instead forms a large pressure-supported envelope which powers optical/UV emission as it undergoes gradual Kelvin-Helmholtz contraction. We present results interpreting a sample of 15 optical TDE within the cooling envelope model in order to constrain the SMBH mass $M_{\rm BH}$, stellar mass $M_{\star}$, and orbital penetration factor $β$. The distributions of inferred properties from our sample broadly follow the theoretical expectations of loss-cone analysis assuming a standard stellar initial mass function. However, we find a deficit of events with $M_{\rm BH} \lesssim 5\times 10^{5}M_{\odot}$ and $M_{\star} \lesssim 0.5M_{\odot}$, which could result in part from the reduced detectability of TDEs with these properties. Our model fits also illustrate the predicted long delay between the optical light curve peak and when the SMBH accretion rate reaches its maximum. The latter occurs only once the envelope contracts to the circularization radius on a timescale of months to years, consistent with delayed-rising X-ray and non-thermal radio flares seen in a growing number of TDE.
format Preprint
id arxiv_https___arxiv_org_abs_2307_15121
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Tidal Disruption Events through the Lens of the Cooling Envelope Model
Sarin, Nikhil
Metzger, Brian D.
High Energy Astrophysical Phenomena
The cooling envelope model for tidal disruption events (TDE) postulates that while the stellar debris streams rapidly dissipate their bulk kinetic energy (``circularize"), this does not necessarily imply rapid feeding of the supermassive black hole (SMBH). The bound material instead forms a large pressure-supported envelope which powers optical/UV emission as it undergoes gradual Kelvin-Helmholtz contraction. We present results interpreting a sample of 15 optical TDE within the cooling envelope model in order to constrain the SMBH mass $M_{\rm BH}$, stellar mass $M_{\star}$, and orbital penetration factor $β$. The distributions of inferred properties from our sample broadly follow the theoretical expectations of loss-cone analysis assuming a standard stellar initial mass function. However, we find a deficit of events with $M_{\rm BH} \lesssim 5\times 10^{5}M_{\odot}$ and $M_{\star} \lesssim 0.5M_{\odot}$, which could result in part from the reduced detectability of TDEs with these properties. Our model fits also illustrate the predicted long delay between the optical light curve peak and when the SMBH accretion rate reaches its maximum. The latter occurs only once the envelope contracts to the circularization radius on a timescale of months to years, consistent with delayed-rising X-ray and non-thermal radio flares seen in a growing number of TDE.
title Tidal Disruption Events through the Lens of the Cooling Envelope Model
topic High Energy Astrophysical Phenomena
url https://arxiv.org/abs/2307.15121