相关论文: Bremsstrahlung Radiation At a Vacuum Bubble Wall
We study the gravitational radiation produced by the collisions of bubble walls or thin fluid shells in cosmological phase transitions. Using the so-called envelope approximation, we obtain analytically the asymptotic behavior of the…
One of the key observables in a gravitational wave power spectrum from a first order phase transition in the early Universe is the mean bubble spacing, which depends on the rate of nucleation of bubbles of the stable phase, as well as the…
The gravitational wave (GW) spectrum from the first-order phase transition can be characterized by a few phenomenological parameters but with high degeneracies in model/data distinguishments. In this paper, we look into the high-frequency…
We present a general method for computing the gravitational radiation arising from the motion of bubble walls or thin fluid shells in cosmological phase transitions. We discuss the application of this method to different wall kinematics. In…
We study the propagation of bubbles of new vacuum in a radially inhomogeneous background filled with dust or radiation, and including a cosmological constant, as a first step in the analysis of the influence of inhomogeneities in the…
We present a model of coherent Bremsstrahlung emission from the compression phase of relativistic heavy ion collisions based on a hydrodynamical description of the collision process. The decceleration of the matter through a shock front,…
We investigate vacuum decays in the early Universe in the presence of curvature perturbations. For sufficiently large perturbations associated with over-densities, we find that the bounce solution develops an oscillating middle stage near…
The walls of bubbles in a first-order phase transition can propagate either as detonations, with a velocity larger than the speed of sound, or deflagrations, which are subsonic. We calculate the gravitational radiation that is produced by…
We discuss a variety of bremsstrahlung processes associated with charged particles emitted by evaporating black holes. We show that such particles produce a negligible number of bremsstrahlung photons from their scattering off each other,…
We investigated the bubble collisions during the first order phase transitions. Numerical results indicate that within the certain range of parameters the collision of two bubbles leads to formation of separate relatively long-lived…
Within the context of a first-order phase transition in the early Universe, we study the collision process for vacuum bubbles expanding in a plasma. The effects of the plasma are simulated by introducing a damping term in the equations of…
The Maxwell field of a charge e which experiences an impulsive acceleration or deceleration is constructed explicitly by subdividing Minkowskian space-time into two halves bounded by a future null-cone and then glueing the halves back…
We consider the processes of polarization bremsstrahlung in collisions of fast ions with linear chains consisting of isolated atoms. We obtained intensities and angular distributions of radiation spectra for arbitrary number of atoms in the…
The cosmological remnants of a first-order phase transition generally depend on the perturbations that the walls of expanding bubbles originate in the plasma. Several of the formation mechanisms occur when bubbles collide and lose their…
Low energy bremsstrahlung formulae are derived for a particle beam of charged bosons forming a Bose-Einsten condensate. The expression for energy radiated consists of two terms in this case. One of them, the larger one in the limit of large…
Our local Hubble volume might be contained within a bubble that nucleated in a false vacuum with only two large spatial dimensions. We study bubble collisions in this scenario and find that they generate gravity waves, which are made…
Classical bremsstrahlung of a massless scalar field $\Phi$ is studied in gravity mediated ultra-relativistic collisions with impact parameter $b$ of two massive point particles in the presence of $d$ non-compact or toroidal extra…
We estimate the dipole radiation emitted in fusion processes. We show that a classical bremsstrahlung approach can account for both the preequilibrium and the thermal photon emission. We give an absolute evaluation of the pre-equilibrium…
Vacuum bubbles, formed in first order phase transitions, have important implications for cosmology. In particular, they source gravitational waves. Usually, it is assumed that, once bubbles are materialized, their state, further evolution…
The radiation at collision of high-energy particles is formed over a rather long distances and therefore is sensitive to an environment. In particular the smallness of the transverse dimensions of the colliding beams leads to suppression of…