Related papers: Sommerfeld enhancement for a Yukawa potential
The annihilation of heavy particles close to thermal equilibrium, which plays a prominent role in the chemical equilibration of heavy quarks in the Quark-Gluon Plasma (QGP) as well as in many classic dark matter scenarios, is reexamined. We…
We apply the idea of giant slow wave resonance associated with a degenerate photonic band edge to gain enhancement of active media. This approach allows to dramatically reduce the size of slow wave resonator while improving its performance…
In this paper, we present the proof of superlensing an arbitrary object using complementary media and we study reflecting complementary media for electromagnetic waves. The analysis is based on the reflecting technique and new results on…
Dark matter with Sommerfeld-enhanced annihilation has been proposed to explain observed cosmic ray positron excesses in the 10 GeV to TeV energy range. We show that the required enhancement implies thermal relic densities that are too small…
If an object is very small in size compared with the wavelength of light, it does not scatter light efficiently. It is hence difficult to detect a very small object with light. We show using analytic theory as well as full wave numerical…
In dark matter coannihilation scenarios, the Sommerfeld effect of coannihilators is usually important in calculations of dark matter thermal relic abundance. Due to decays of coannihilators, two annihilating coannihilators can only approach…
Recently, we have discovered a new concept of permanent wave resonance with potential spatial oscillations. This means the constant wave swinging frequency on the whole energy intervals of spectral forbidden zones destroying physical…
Recent observations indicate that core-like dark matter structures exist in many galaxies, while numerical simulations reveal a singular dark matter density profile at the center. In this article, I show that if the annihilation of dark…
Much attention has been given to dark matter explanations of the PAMELA positron fraction and Fermi electronic excesses. For those theories with a TeV-scale WIMP annihilating through a light force-carrier, the associated Sommerfeld…
A method for solving the half-space Sommerfeld problem is proposed, which allows us to obtain exact solutions in the form of Sommerfeld integrals, as well as their short-wave asymptotics. The first carried out by reducing the Sommerfeld…
We report on the experimental observation of the beaming effect in photonic crystals enhanced via surface modes. We experimentally map the spatial field distribution of energy emitted from a subwavelength photonic crystal waveguide into…
The simulation of light scattering by particles on a substrate with the $T$-matrix method relies on the expansion of the scattered field in spherical waves, followed by a plane wave expansion to allow the evaluation of the reflection from…
Sommerfeld enhancement and Breit-Wigner enhancement of the dark matter annihilation have been proposed to explain the "boost factor" which is suggested by observed cosmic ray excesses. Although these two scenarios can provide almost…
We construct explicit models of particle dark matter where the attractive force in the dark matter sector creates a narrow near-threshold resonance that qualitatively changes the energy dependence of the annihilation cross section. In these…
A new effective field theory has been developed to describe shallow $P$-wave resonances using nonlocal, momentum-dependent two-body potentials. This approach is expected to facilitate many-body calculations and has been demonstrated to…
We present a comprehensive study on the self-interaction cross-section of puffy dark matter (DM) particles, which have a significant intrinsic size compared to their Compton wavelength. For such puffy DM self-interaction cross-section in…
We show that the presence of nearby Coulombic resonances at finite energy could lead to the enhancement of the dark matter annihilation cross section at specific non-zero velocities correlated with the mass splitting between the dark matter…
We report on some recent work, which points out the relevance of future measurements of gravitational waves by resonant-mass detectors of spherical shape for theories of gravity of non-Einstein type.
A recent research shows that particles with a spectrum of a relativistic Maxwellian plus a high-energy tail can be accelerated by relativistic collisionless shocks. We investigate the possibility of the high-energy particles with this new…
Localized surface plasmons are charge density oscillations confined to metallic nanoparticles. Excitation of localized surface plasmons by an electromagnetic field at an incident wavelength where resonance occurs results in a strong light…