Once a Giant, (Almost) Always a Giant: Partial Tidal Disruption Events of Giant Stars

Tidal disruption events (TDEs) of giant stars by supermassive black holes (SMBH) differ significantly from those of main-sequence ones. Most (all for SMBH of more than a few ×10 ^5 m _⊙ ) giant TDEs are partial: only a fraction of the envelope is torn apart. The dense stellar core and the rest of th...

Full description

Saved in:
Bibliographic Details
Main Authors: Núria Navarro Navarro, Tsvi Piran
Format: Article
Language:English
Published: IOP Publishing 2025-01-01
Series:The Astrophysical Journal
Subjects:
Online Access:https://doi.org/10.3847/1538-4357/ad96b7
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850183001833472000
author Núria Navarro Navarro
Tsvi Piran
author_facet Núria Navarro Navarro
Tsvi Piran
author_sort Núria Navarro Navarro
collection DOAJ
description Tidal disruption events (TDEs) of giant stars by supermassive black holes (SMBH) differ significantly from those of main-sequence ones. Most (all for SMBH of more than a few ×10 ^5 m _⊙ ) giant TDEs are partial: only a fraction of the envelope is torn apart. The dense stellar core and the rest of the envelope remain intact. In this work we explore, using the stellar evolution code MESA , the fate of the remnants. We find that after a short period, comparable to the thermal timescale, the remnant returns to a giant structure with a radius comparable to the progenitor giant one, a slightly larger luminosity (as compared with a regular giant with the same mass), and a comparable lifetime until it collapses to a white dwarf. If such a giant with a mass less than ≈0.9 m _⊙ is discovered, it can be identified as an outlier—a giant that is too light for the current age of the Universe. If the remnant orbit is not perturbed significantly during the encounter, the remnant will undergo successive partial tidal disruptions until its mass is 0.6–0.7 m _⊙ . We expect a few dozen to a few hundred such remnants in the Galactic nucleus.
format Article
id doaj-art-59d169620fc448e4b9b090dcbfec690e
institution OA Journals
issn 1538-4357
language English
publishDate 2025-01-01
publisher IOP Publishing
record_format Article
series The Astrophysical Journal
spelling doaj-art-59d169620fc448e4b9b090dcbfec690e2025-08-20T02:17:28ZengIOP PublishingThe Astrophysical Journal1538-43572025-01-01983217710.3847/1538-4357/ad96b7Once a Giant, (Almost) Always a Giant: Partial Tidal Disruption Events of Giant StarsNúria Navarro Navarro0https://orcid.org/0009-0003-0566-3401Tsvi Piran1https://orcid.org/0000-0002-7964-5420Racah Institute for Physics, The Hebrew University , Jerusalem, 91904, Israel ; nuria.navarronav@mail.huji.ac.il, tsvi.piran@mail.huji.ac.ilRacah Institute for Physics, The Hebrew University , Jerusalem, 91904, Israel ; nuria.navarronav@mail.huji.ac.il, tsvi.piran@mail.huji.ac.ilTidal disruption events (TDEs) of giant stars by supermassive black holes (SMBH) differ significantly from those of main-sequence ones. Most (all for SMBH of more than a few ×10 ^5 m _⊙ ) giant TDEs are partial: only a fraction of the envelope is torn apart. The dense stellar core and the rest of the envelope remain intact. In this work we explore, using the stellar evolution code MESA , the fate of the remnants. We find that after a short period, comparable to the thermal timescale, the remnant returns to a giant structure with a radius comparable to the progenitor giant one, a slightly larger luminosity (as compared with a regular giant with the same mass), and a comparable lifetime until it collapses to a white dwarf. If such a giant with a mass less than ≈0.9 m _⊙ is discovered, it can be identified as an outlier—a giant that is too light for the current age of the Universe. If the remnant orbit is not perturbed significantly during the encounter, the remnant will undergo successive partial tidal disruptions until its mass is 0.6–0.7 m _⊙ . We expect a few dozen to a few hundred such remnants in the Galactic nucleus.https://doi.org/10.3847/1538-4357/ad96b7Tidal disruptionRed giant starsAstrophysical black holesGalactic center
spellingShingle Núria Navarro Navarro
Tsvi Piran
Once a Giant, (Almost) Always a Giant: Partial Tidal Disruption Events of Giant Stars
The Astrophysical Journal
Tidal disruption
Red giant stars
Astrophysical black holes
Galactic center
title Once a Giant, (Almost) Always a Giant: Partial Tidal Disruption Events of Giant Stars
title_full Once a Giant, (Almost) Always a Giant: Partial Tidal Disruption Events of Giant Stars
title_fullStr Once a Giant, (Almost) Always a Giant: Partial Tidal Disruption Events of Giant Stars
title_full_unstemmed Once a Giant, (Almost) Always a Giant: Partial Tidal Disruption Events of Giant Stars
title_short Once a Giant, (Almost) Always a Giant: Partial Tidal Disruption Events of Giant Stars
title_sort once a giant almost always a giant partial tidal disruption events of giant stars
topic Tidal disruption
Red giant stars
Astrophysical black holes
Galactic center
url https://doi.org/10.3847/1538-4357/ad96b7
work_keys_str_mv AT nurianavarronavarro onceagiantalmostalwaysagiantpartialtidaldisruptioneventsofgiantstars
AT tsvipiran onceagiantalmostalwaysagiantpartialtidaldisruptioneventsofgiantstars