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Abstract Through numerical simulations of boson-star head-on collisions, we explore the quality of binary initial data obtained from the superposition of single-star spacetimes. Our results demonstrate that evolutions starting from a plain superposition of individual boosted boson-star spacetimes are vulnerable to significant unphysical artefacts. For equal-mass binaries, these difficulties can be overcome with a simple modification of the initial data suggested in Helferet al(2019Phys. Rev. D99044046) for collisions of oscillations. While we specifically consider massive complex scalar field boson star models of very high and low compactness, we conjecture that this vulnerability be also present in other kinds of exotic compact systems and hence needs to be addressed.
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Unequal-mass boson-star binaries: initial data and merger dynamics
Abstract We present a generalisation of the curative initial data construction derived for equal-mass compact binaries in Helferet al(2019Phys. Rev.D99044046; 2022Class. Quantum Grav.39074001) to arbitrary mass ratios. We demonstrate how these improved initial data avoid substantial spurious artifacts in the collision dynamics of unequal-mass boson-star binaries in the same way as has previously been achieved with the simpler method restricted to the equal-mass case. We employ the improved initial data to explore in detail the impact of phase offsets in the coalescence of equal- and unequal-mass boson star binaries.
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- Award ID(s):
- 2006538
- PAR ID:
- 10402701
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Classical and Quantum Gravity
- Volume:
- 40
- Issue:
- 8
- ISSN:
- 0264-9381
- Page Range / eLocation ID:
- Article No. 085009
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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