Related papers: Graviton-induced Bremsstrahlung at e^+e^- collider…
First quasiclassical correction to the differential cross section of high-energy electron-positron photoproduction in the electric field of a heavy atom is obtained with the exact account of the field. This correction is responsible for the…
We compute the spectra of bremsstrahlung photons for different stopping scenarios which give rise to different initial charge-rapidity distributions. In the light of novel experimental opportunities that may arise with a new heavy-ion…
Astrophysical bounds severely limit the possibility of observing collider signals of gravity with less than 3 flat extra dimensions. However, small distortions of the compactified space can lift the masses of the lightest graviton…
We explore the potential of future high-energy lepton colliders to probe heavy vector resonances. At wakefield colliders, intense beam-beam interactions produce radiation, called beamstrahlung, which redistributes luminosity from the…
The low $p_T$ direct photon production from a variety of the hadronic sources is studied within the microscopic HSD transport approach for p+C, p+Pb and Pb+Pb collisions at 160 A GeV. The direct photon emission from elementary hadronic…
A coupling of a dark photon $A'$ from a $U(1)_{A'}$ with the standard model (SM) particles can be generated through kinetic mixing represented by a parameter $\epsilon$. A non-zero $\epsilon$ also induces a mixing between $A'$ and $Z$ if…
The radiation reaction (beamstrahlung) effect on particle dynamics during interaction of oppositely charged beams is studied. It is shown that the beam focusing can be strongly enhanced due to beamstrahlung. An approximate analytical…
We study the possibility of uniquely identifying the effects of graviton exchange from other new physics in high energy e^+e^- annihilation into fermion-pairs. For this purpose, we use as basic observable a specific asymmetry among…
We study gravitational lensing and the bending of light in low energy scale (M_S) gravity theories with extra space-time dimensions n. We find that due to the presence of spin-2 Kaluza-Klein states from compactification, a correction to the…
Graviton-photon oscillation is the conversion of gravitational waves to electromagnetic waves and vice versa in the presence of a background electromagnetic field. We investigate this phenomenon in a cosmological scenario considering a…
In the energy domain of 1-2 GeV per nucleon, HADES has measured rare penetrating probes (e+e-) in C+C, Ar+KCl, d+p, p+p and p+Nb collisions. For the first time the electron pairs were reconstructed from quasi-free n+p sub-reactions by…
High energy photon colliders (gamma-gamma, gamma-electron) based on backward Compton scattering of laser light is a very natural addition to e+e- linear colliders. In this report we consider mainly this option for the TESLA project. Recent…
We reveal that the energy spectra of electrons-positrons in primary cosmic rays measured at atmosphere top have double structures: an excess component $\Phi^s_{e^+}(E)=\Phi^s_{e^-}(E)$ around $400 GeV$, which origins from a strong…
Dilepton production provides a unique probe of the strong electromagnetic field produced in heavy-ion collisions. To map out the behavior of its transverse momentum broadening, we present a theoretical model based on the equivalent photon…
The Randall-Sundrum (RS) model with a small curvature is considered. The mass spectrum of Kaluza-Klein (KK) gravitons in such a scheme is similar (although not equivalent) to that in a model with one extra dimension in a flat metric. The…
We study the sensitivity reach of $0.5-2$ TeV $e^+ e^-$ linear colliders in the context of the ADD model, in which gravity becomes strong at TeV scale. We include the real emission channel $e^+ e^- \to \gamma G$, as well as the…
The complementarity of $e^+e^-$ and $\gamma \gamma$ colliders to discover and explore new physics beyond the Standard Model(SM) is discussed. After briefly surveying a number of various new physics scenarios we concentrate in detail on…
Coherent peripheral collisions of atomic nuclei involve electromagnetic or long range hadronic interactions at impact parameters, where both nuclei survive intact. Recently such ultra-peripheral collisions were observed at RHIC. The effect…
We evaluate the prospects for measuring $BR(h\to\gamma\gamma)$ for a Standard-Model-like Higgs boson at the Next Linear $e^+e^-$ Collider in the $e^+e^-\to Z^*\to Z h$ and $e^+e^-\to\nu_e\anti\nu_e h$ production modes. Relative merits of…
Inclusive double differential multiplicities of deuterons, ^3H, ^3He, and ^4He measured by E877 for 11.5 A GeV/c Au+Au collisions at the AGS are presented. Light fragments at beam-rapidity are measured for the first time at AGS energies.…