Condensation and evaporation of boson stars

Condensation and evaporation of boson stars

Blog Article

Abstract Axion-like particles, including the QCD axion, are well-motivated Other Panels dark matter candidates.Numerical simulations have revealed coherent soliton configurations, also known as boson stars, in the centers of axion halos.We study evolution of axion solitons immersed into a gas of axion waves with Maxwellian velocity distribution.

Combining analytical approach with controlled numerical simulations we find that heavy solitons grow by condensation of axions from the gas, while light solitons evaporate.We deduce the parametric dependence of the soliton growth/evaporation rate and show that it is proportional to the rate of the kinetic relaxation in the gas.The proportionality coefficient is controlled by the product of the soliton radius and the typical gas momentum or, equivalently, the ratio of DONG QUAI ROOT C/S the gas and soliton virial temperatures.

We discuss the asymptotics of the rate when this parameter is large or small.