Hot Jupiter engulfment by a red giant in 3D hydrodynamics

Fuente: arXiv
Gespeichert in:
Bibliographische Detailangaben
Hauptverfasser: Lau, Mike Y. M., Cantiello, Matteo, Jermyn, Adam S., MacLeod, Morgan, Mandel, Ilya, Price, Daniel J.
Format: Preprint
Veröffentlicht: 2022
Schlagworte:
Online-Zugang:
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
_version_ 1866915158607003648
author Lau, Mike Y. M.
Cantiello, Matteo
Jermyn, Adam S.
MacLeod, Morgan
Mandel, Ilya
Price, Daniel J.
author_facet Lau, Mike Y. M.
Cantiello, Matteo
Jermyn, Adam S.
MacLeod, Morgan
Mandel, Ilya
Price, Daniel J.
contents Hot Jupiters are gas giant planets with orbital periods of a few days and are found in 0.1-1% of Sun-like stars. They are expected to be engulfed during their host star's radial expansion on the red giant branch, which may account for observed rapidly rotating and chemically enriched giant stars. We performed 3D hydrodynamical simulations of hot Jupiter engulfment by a 1 solar mass, 4 solar radii early red giant. Our 'global' simulations simultaneously resolve the stellar envelope and planetary structure, modelling the hot Jupiter as a polytropic gas sphere. The hot Jupiter spirals in due to ram-pressure drag. A substantial fraction of its mass is continuously ablated in this process, although the mass-loss rate is resolution dependent. We estimate that this could enhance the surface lithium abundance by up to 0.1 dex. The hot Jupiter is disrupted by a combination of ram pressure and tidal forces near the base of the convective envelope, with the deepest material penetrating to the radiative zone. The star experiences modest spin-up (~ 1 km/s), and engulfing a more massive companion may be required to produce a rapidly rotating giant. Drag heating near the surface and hydrogen recombination in the small amount of unbound ejecta recorded in the simulation could power an optical transient, although this needs to be confirmed by a calculation that has adequate resolution at the stellar surface.
format Preprint
id arxiv_https___arxiv_org_abs_2210_15848
institution arXiv
publishDate 2022
record_format arxiv
spellingShingle Hot Jupiter engulfment by a red giant in 3D hydrodynamics
Lau, Mike Y. M.
Cantiello, Matteo
Jermyn, Adam S.
MacLeod, Morgan
Mandel, Ilya
Price, Daniel J.
Solar and Stellar Astrophysics
Earth and Planetary Astrophysics
Hot Jupiters are gas giant planets with orbital periods of a few days and are found in 0.1-1% of Sun-like stars. They are expected to be engulfed during their host star's radial expansion on the red giant branch, which may account for observed rapidly rotating and chemically enriched giant stars. We performed 3D hydrodynamical simulations of hot Jupiter engulfment by a 1 solar mass, 4 solar radii early red giant. Our 'global' simulations simultaneously resolve the stellar envelope and planetary structure, modelling the hot Jupiter as a polytropic gas sphere. The hot Jupiter spirals in due to ram-pressure drag. A substantial fraction of its mass is continuously ablated in this process, although the mass-loss rate is resolution dependent. We estimate that this could enhance the surface lithium abundance by up to 0.1 dex. The hot Jupiter is disrupted by a combination of ram pressure and tidal forces near the base of the convective envelope, with the deepest material penetrating to the radiative zone. The star experiences modest spin-up (~ 1 km/s), and engulfing a more massive companion may be required to produce a rapidly rotating giant. Drag heating near the surface and hydrogen recombination in the small amount of unbound ejecta recorded in the simulation could power an optical transient, although this needs to be confirmed by a calculation that has adequate resolution at the stellar surface.
title Hot Jupiter engulfment by a red giant in 3D hydrodynamics
topic Solar and Stellar Astrophysics
Earth and Planetary Astrophysics
url https://arxiv.org/abs/2210.15848