相关论文: Effective photon spectra for Photon Colliders
The moments of the photon spectrum in the inclusive $B\to X_s\,\gamma$ decay can be calculated to order $\alpha_s$ accuracy at present, without knowing the $\alpha_s$ corrections to the effective Hamiltonian. We discuss the standard model…
Light-by-light scattering is a relatively new area of experimental physics. Our recent, theoretical research shows that studying two photon measurements in regions with lower transverse momentum ($p_{t,\gamma}$) and invariant mass…
The possibility of a Photon-Photon collider extension to the Beam dump of the $17.5$ GeV European XFEL has been discussed before as the first high energy collider of its sort. It would not just be to study the concept of photon colliders…
We present cross sections for the production of the lightest supersymmetric particle as a neutralino state in the minimal supersymmetric standard model at electron-photon colliders. The lightest supersymmetric particle mass is taken at a…
A correlation between the peak luminosity and the peak energy has been found by Yonetoku et al. as $L_{p}\propto E_{p,i}^{2.0}$ for 11 pre-Swift long gamma-ray bursts. In this study, for a greatly expanded sample of 148 long gamma-ray…
We describe the resonant interaction of an atom with a strongly focused light beam by expanding the field in multipole waves. For a classical field, or when the field is described by a coherent state, we find that both intensity pattern and…
In this note, as an input to the Snowmass studies, we provide a broad-brush picture of the physics output of future colliders as a function of their center of mass energies and luminosities. Instead of relying on precise projections of…
We quantify the discovery potential of future multi-TeV plasma wakefield colliders for new electroweak multiplets. We include beam-beam effects through realistic luminosity spectra, comparing five collider configurations: $e^+e^-$ and…
The radiation of photons by electrons is investigated in the framework of quantum electrodynamics up to the second order in the coupling constant $e$. The $N$-particle, coherent, and thermal initial states are considered and the forms of…
In an ideal germanium detector, fully-absorbed monoenergetic gamma-rays will appear in the measured spectrum as a narrow peak, broadened into a Gaussian of width determined only by the statistical properties of charge cloud generation and…
The particle production in photon-photon ($\gamma \gamma$) interactions present in electron-ion collisions is investigated. We present calculations for the total cross sections and event rates related to the production of light mesons…
We discuss a possibility of detecting a coherent photon pair emission and related radiative neutrino pair emission from excited atoms. It is shown that atoms of lambda- and ladder-type three level system placed in a pencil-like cylinder…
In this paper the two-photon interactions at high energies are investigated considering different approaches for the QCD dynamics. In particular, we calculate the $\gamma^* \gamma^*$ total cross section in different theoretical approches…
Based on current CERN infrastructure, an electron--proton collider is proposed at a centre-of-mass energy of about 9 TeV. A 7 TeV LHC bunch is used as the proton driver to create a plasma wakefield which then accelerates electrons to…
We calculate the mean power spectrum of galaxies using published power spectra of galaxies and clusters of galaxies. On small scales we use the power spectrum derived from the 2-dimensional distribution of APM galaxies, on large scales we…
We present a physical framework that can account for most of the observed spectral properties of the prompt gamma-ray burst emission. This includes the variety of spectral shapes, shape evolutions, and spectral correlations between flux and…
The thermodynamical properties of the photon-plasma system had been studied using statistical physics approach. Photons develop an effective mass in the medium thus -- as a result of the finite chemical potential -- a photon Bose-Einstein…
Examination of equilibrium radiation in plasma media shows that the spectral energy distribution of such radiation is different from the Planck equilibrium radiation. Using the approach of quantum electrodynamics the general relation for…
If the gravitino G is very light and all the other supersymmetric particles are above threshold, supersymmetry may still be found at colliders, by looking at processes with only gravitinos and ordinary particles in the final state. We…
Due to the coherence of all the protons in a nucleus, there are very strong electromagnetic fields of short duration in relativistic heavy ion collisions. They give rise to quasireal photon-photon and photon-nucleus collisions with a large…