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Title: Mass Ejection Driven by Sudden Energy Deposition in Stellar Envelopes
Abstract

A number of stellar astrophysical phenomena, such as tidal novae and planetary engulfment, involve sudden injection of subbinding energy in a thin layer within the star, leading to mass ejection of the stellar envelope. We use a 1D hydrodynamical model to survey the stellar response and mass loss for various amounts (Edep) and locations of the energy deposition. We find that the total mass ejection has a nontrivial dependence onEdepdue to the varying strengths of mass ejection events, which are associated with density/pressure waves breaking out from the stellar surface. The rapid occurrence of multiple breakouts may present a unique observational signature for sudden envelope heating events in stars.

 
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PAR ID:
10507608
Author(s) / Creator(s):
;
Publisher / Repository:
DOI PREFIX: 10.3847
Date Published:
Journal Name:
The Astrophysical Journal
Volume:
967
Issue:
1
ISSN:
0004-637X
Format(s):
Medium: X Size: Article No. 33
Size(s):
Article No. 33
Sponsoring Org:
National Science Foundation
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