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arXiv · 1805.11488

$\ell$-Boson stars

Miguel Alcubierre·Juan Barranco·Argelia Bernal·Juan Carlos Degollado·Alberto Diez-Tejedor·Miguel Megevand·Dario Nunez·Olivier Sarbach
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Abstract

We present new, fully nonlinear numerical solutions to the static, spherically symmetric Einstein-Klein-Gordon system for a collection of an arbitrary odd number $N$ of complex scalar fields with an internal $U(N)$ symmetry and no self-interactions. These solutions, which we dub $\ell$-boson stars, are parametrized by an angular momentum number $\ell=(N-1)/2$, an excitation number $n$, and a continuous parameter representing the amplitude of the fields. They are regular at every point and possess a finite total mass. For $\ell = 0$ the standard spherically symmetric boson stars are recovered. We determine their generalizations for $\ell > 0$, and show that they give rise to a large class of new static configurations which might have a much larger compactness ratio than $\ell=0$ stars.

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BibTeXRIS

Miguel Alcubierre, Juan Barranco, Argelia Bernal, Juan Carlos Degollado, Alberto Diez-Tejedor, Miguel Megevand, Dario Nunez, Olivier Sarbach. 2018-05-29. $\ell$-Boson stars. https://doi.org/10.1088/1361-6382%2Faadcb6

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