相关论文: Decay of light baryons by soft photon emission
The decay of photon by the influence of magnetic field is considered. It is shown here that if the photon energy is grater than 1 MeV then photon can decay electron positron pair, but if it remains below 1 MeV then photon decays into…
An attractive way to generate neutrino masses as required to account for current neutrino oscillation data involves the spontaneous breaking of lepton number. The resulting majoron may pick up a mass due to gravity. If its mass lies in the…
Heavy ions at high velocities provide very strong electromagnetic fields for a very short time. The main characteristics of ultraperipheral relativistic heavy ion collisions are reviewed, characteristic parameters are identified. The main…
In this note, we discuss the derivation of a formula that has been used in the literature in order to compute the number of photons emitted by a hot or dense system during a finite time. Our derivation is based on a variation of the…
We present some bottom-up motivations of axions and other weakly interacting sub-eV particles (WISPs) coupling to photons. Typically, these light particles are strongly constrained by their production or interaction in astrophysical and…
Inelastic pp collisions are dominated by soft (low momentum transfer) physics where perturbative QCD cannot be fully applied. A deep understanding of both soft and semi-hard processes is crucial for predictions of minimum bias and…
A scheme of soft-xray radiation is proposed. In the scheme, a moderately intense laser excites plasmons via the two-plasmon decay in a relativistic electron beam. As the second laser encounters the electron beam in the opposite direction,…
The process of hard photon emission by initial electrons (positrons) at B-factories is discussed. It is shown that studies of the bottomonium spectroscopy will be feasible for the planned integrated luminosity of the B-factory experiments.
A detailed study of various two-particle correlation functions involving photons and neutral pions is presented in proton-proton and lead-lead collisions at the LHC energy. The aim is to use these correlation functions to quantify the…
Productions of soft photon with low transverse momenta in high-energy hadron-hadron collisions and $e^+$-$e^-$ annihilations indicate that they are consistently produced in excess of what are predicted by electromagnetic bremsstrahlung when…
There are currently several proposals to build a high-luminosity electron-ion collider, to study the spin structure of matter and measure parton densities in heavy nuclei, and to search for gluon saturation and new phenomena like the…
I discuss the parton distributions in the photon and the constraints coming from the jet production in photoproduction and in photon-photon collisions.
We discuss the characteristic interference features of soft radiation in the threshold production of heavy unstable particles: soft gluon radiation in $\ee \to \tt$ and soft photon radiation in $\ee \to \ww$. We show that the heavy particle…
A new effect is presented, which changes the emittance during colliding-beam operation in circular colliders. If the initial transverse distribution is Gaussian, the collision probability is much higher for particles in the core of the beam…
We have used ROSAT PSPC and HRI to study the properties of the soft X-ray emission in a sample of colliding starburst galaxies. Together with data from other spectral ranges (optical, radio and FIR) we investigate the emergence of soft…
We expose the role of collisional energy loss on high $p_T$ photon data measured by PHENIX collaboration by calculating photon yield in jet plasma interaction. The phase space distribution of the participating jet is dynamically evolved by…
We propose an explanation of the galactic center gamma ray excess by supersymmetric WIMPs as heavy as 500 GeV. The lightest neutralino annihilates into vector-like leptons or quarks which cascade decay through intermediate Higgs bosons. Due…
We calculate the production of J/psi mesons by neutrino-nucleon collisions in fixed target experiments. Soft color, often referred to as color evaporation effects, enhance production cross sections due to the contribution of color octet…
We discuss real and virtual photon sources in heavy ion collisions and present results for dilepton yields in Pb+Pb collisions at the LHC at intermediate and large transverse momentum p_T.
Particle acceleration in plasma creates a possibility of exceptionally high accelerating gradients and appears as a very attractive option for future linear electron-positron and/or photon-photon colliders. These high accelerating gradients…