Dense Axion Stars.

  title={Dense Axion Stars.},
  author={Eric Braaten and Abhishek Ray Mohapatra and Hong Zhang},
  journal={Physical review letters},
  volume={117 12},
If the dark matter particles are axions, gravity can cause them to coalesce into axion stars, which are stable gravitationally bound systems of axions. In the previously known solutions for axion stars, gravity and the attractive force between pairs of axions are balanced by the kinetic pressure. The mass of these dilute axion stars cannot exceed a critical mass, which is about 10^{-14}M_{⊙} if the axion mass is 10^{-4}  eV. We study axion stars using a simple approximation to the effective… Expand
Axion Stars
  • H. Zhang
  • Physics, Computer Science
  • Symmetry
  • 2020
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Axion-like particles lead to a plethora of new phenomena relating to compact astrophysical objects including stellar and black hole superradiance, axion stars and axion clusters. In this work, weExpand
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Axions are some of the best motivated particles beyond the Standard Model. We show how the attractive self-interactions of dark matter (DM) axions over a broad range of masses, from $10^{-22}$ eV toExpand
Detecting Axion Stars with Radio Telescopes
Abstract When axion stars fly through an astrophysical magnetic background, the axion-to-photon conversion may generate a large electromagnetic radiation power. After including the interferenceExpand


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We analyze the behavior of axion dark matter before it falls into a galactic gravitational potential well. The axions thermalize sufficiently fast by gravitational self-interactions that almost allExpand
Axion stars in the infrared limit
A bstractFollowing Ruffini and Bonazzola, we use a quantized boson field to describe condensates of axions forming compact objects. Without substantial modifications, the method can only be appliedExpand
Bose-Einstein condensation of dark matter axions.
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Self-gravitating system made of axions
We show that the inclusion of an axionlike effective potential in the construction of a self-gravitating system of scalar fields decreases its compactness when the value of the self-interactionExpand
Axion miniclusters and Bose stars.
  • Kolb, Tkachev
  • Physics, Medicine
  • Physical review letters
  • 1993
It is found that perturbations on scales corresponding to causally disconnected regions at T T GeV can lead to very dense axion clumps, with present density high enough for the collisional 2a\ensuremath{\rightarrow}2a process to lead to Bose-Einstein relaxation in the gravitationally bound clumps of axions, forming Bose stars. Expand
On the possibility of Bose-star formation
Abstract The relaxation time of a gravitationally bounded cloud of bosons is estimated for the case of a large phase-space density of particles. The axionic mass and self-coupling relaxation time areExpand
Axion dark matter and cosmological parameters.
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