Related papers: Axions and the Galactic Angular Momentum Distribut…
Axions as dark matter is an increasingly important subject in astrophysics and cosmology. Experimental and observational searches are mounting across the mass spectrum of axion-like particles, many of which require detailed knowledge of…
In a spherically symmetric plasma constrained by its own gravity, the ionization degree lags behind changes in temperature and density. The ambipolar electric field accelerates ions radially and cools electrons. Ions lose energy and angular…
We explore the viability of a boson dark matter candidate with an asymmetry between the number densities of particles and antiparticles. A simple thermal field theory analysis confirms that, under certain general conditions, this component…
The behavior of light scalar dark matter has been a subject of much interest recently as it can lead to interesting small scale behavior. In particular, this can lead to the formation of gravitationally bound clumps for these light scalars,…
We analyze the rotation curves that correspond to a Bose--Einstein Condensate (BEC) type halo surrounding a Schwarzschild--type black hole to confront predictions of the model upon observations of galaxy rotation curves. We model the halo…
This is a brief review on the history of the Bose-Einstein condensate (BEC) or boson star model of galactic dark matter halos, where ultra-light scalar dark matter particles condense in a single BEC quantum state. The halos can be described…
The axion-like particles with ultralight mass ($\sim10^{-22}$eV) can be a possible candidate of dark matter, known as the fuzzy dark matter (FDM). These particles form Bose-Einstein condensate in the early Universe which can explain the…
The spontaneous formation of lattice structure of quantized vortices is a characteristic feature of superfluidity in closed systems under thermal equilibrium. In exciton-polariton Bose-Einstein condensate, which is a typical example of…
We study the stochastic axion dark matter scenario in the axion landscape, where one of the axions is light and stable and therefore explains dark matter. If the axion mass at the potential is a typical value of the curvature along the…
Infall of cold dark matter on a galaxy may result in caustic rings where the particle density is enhanced. They may be searched for as features in the galactic rotation curves. Previous studies suggested the evidence for these caustic rings…
We consider a Bose-Einstein condensate (BEC) of $N$ atoms of repulsive interaction $\sim U_0$, in an elliptical trap, axially pierced by a Gaussian-intensity laser beam, forming an effective (quasi-2D) toroidal trap with minimum at radial…
Ultra-light bosonic dark matter (ULDM) is an interesting and promising dark matter candidate. While the wave-like nature of ULDM has been widely studied in the literature, we explore another distinctive feature of ULDM as Bose-Einstein…
Ultra-light dark matter may consist of axion-like particles with masses below 10^(-19) eV. Two-photon interactions of these particles affect the polarization of radiation propagating through the dark matter. Coherent oscillations of the…
Most matter in the Universe is invisible and unknown, which is called dark matter. A candidate of dark matter is axion, which is an ultra-light particle motivated as a solution for the CP problem. Axions form clouds in a galactic halo,…
We study the angular momentum profiles both for dark matter and for gas within virialized halos, using a statistical sample of halos drawn from cosmological hydrodynamics simulations. Three simulations have been analyzed, one is the…
We review current cosmological constraints on the axion. We describe the basic mechanisms by which axions are created in the early universe, focussing on the standard thermal scenario where the dominant process is through axion radiation by…
Generating axion dark matter through the kinetic misalignment mechanism implies the generation of large asymmetries for Standard Model fermions in the early universe. Even if these asymmetries are washed out at later times, they can trigger…
If dark matter is mainly composed of axions, the density distribution can be nonuniformly distributed, being clumpy instead. By solving the Einstein-Klein-Gordon system of a scalar field with the potential energy density of an axionlike…
We study the full-sky distribution of the radio emission from the stimulated decay of axions which are assumed to compose the dark matter in the Galaxy. Besides the constant extragalactic and CMB components, the decays are stimulated by a…
For the minimal QCD axion model it is generally believed that overproduction of dark matter constrains the axion mass to be above a certain threshold, or at least that the initial misalignment angle must be tuned if the mass is below that…