TY - JOUR

T1 - Interaction between bosonic dark matter and stars

AU - Brito, Richard

AU - Cardoso, Vitor

AU - Macedo, Caio F. B.

AU - Okawa, Hirotada

AU - Palenzuela, Carlos

PY - 2016/2/16

Y1 - 2016/2/16

N2 - We provide a detailed analysis of how bosonic dark matter "condensates" interact with compact stars, extending significantly the results of a recent Letter [1]. We focus on bosonic fields with mass m(B), such as axions, axion-like candidates and hidden photons. Self-gravitating bosonic fields generically form "breathing" configurations, where both the spacetime geometry and the field oscillate, and can interact and cluster at the center of stars. We construct stellar configurations formed by a perfect fluid and a bosonic condensate, and which may describe the late stages of dark matter accretion onto stars, in dark-matter-rich environments. These composite stars oscillate at a frequency which is a multiple of f = 2.5 x 10(14) (m(B)c(2)/eV) Hz. Using perturbative analysis and numerical relativity techniques, we show that these stars are generically stable, and we provide criteria for instability. Our results also indicate that the growth of the dark matter core is halted close to the Chandrasekhar limit. We thus dispel a myth concerning dark matter accretion by stars: dark matter accretion does not necessarily lead to the destruction of the star, nor to collapse to a black hole. Finally, we argue that stars with long-lived bosonic cores may also develop in other theories with effective mass couplings, such as (massless) scalar-tensor theories.

AB - We provide a detailed analysis of how bosonic dark matter "condensates" interact with compact stars, extending significantly the results of a recent Letter [1]. We focus on bosonic fields with mass m(B), such as axions, axion-like candidates and hidden photons. Self-gravitating bosonic fields generically form "breathing" configurations, where both the spacetime geometry and the field oscillate, and can interact and cluster at the center of stars. We construct stellar configurations formed by a perfect fluid and a bosonic condensate, and which may describe the late stages of dark matter accretion onto stars, in dark-matter-rich environments. These composite stars oscillate at a frequency which is a multiple of f = 2.5 x 10(14) (m(B)c(2)/eV) Hz. Using perturbative analysis and numerical relativity techniques, we show that these stars are generically stable, and we provide criteria for instability. Our results also indicate that the growth of the dark matter core is halted close to the Chandrasekhar limit. We thus dispel a myth concerning dark matter accretion by stars: dark matter accretion does not necessarily lead to the destruction of the star, nor to collapse to a black hole. Finally, we argue that stars with long-lived bosonic cores may also develop in other theories with effective mass couplings, such as (massless) scalar-tensor theories.

KW - ROTATING RELATIVISTIC STARS

KW - FERMION STARS

KW - SCALAR THEORIES

KW - NEUTRON-STARS

KW - STABILITY

KW - CONFIGURATIONS

KW - SIGNATURES

KW - PARTICLES

KW - EQUATIONS

KW - OSCILLONS

U2 - 10.1103/PhysRevD.93.044045

DO - 10.1103/PhysRevD.93.044045

M3 - Journal article

VL - 93

JO - Physical Review D

JF - Physical Review D

SN - 2470-0010

IS - 4

M1 - 044045

ER -