Related papers: Medium Effects in rho-Meson Photoproduction
We present a computation, within weakly-coupled thermal QCD, of the production rate of low invariant mass ($M^2 \sim g^2 T^2$) dileptons, at next-to-leading order (NLO) in the coupling (which is $O(g^3 e^2 T^2)$). This involves extending…
We discuss the status of calculating in-medium modifications of vector-meson spectral functions in hot and dense matter, their application to dilepton spectra in ultrarelativistic heavy-ion collisions, and possible relations to chiral…
We report on dilepton measurements for central Pb on Au collisions at the top CERN SPS energy with the upgraded CERES experiment. The dilepton mass spectrum of 2000 data with improved mass resolution shows an enhancement over the…
We extend our recent analysis of the dilepton and photon emission rates to the case of finite temperature and baryon density, within the context of a density expansion. To leading order, the effects of the baryon density are assessed using…
We report on the results of our recent research published in [1] that shows that AdS/QCD generates predictions for the rate of diffractive \rho-meson electroproduction that are in agreement with data collected at the HERA electron-proton…
We discuss the latest theoretical results on direct photon and dilepton production from relativistic heavy-ion collisions. While the dilepton spectra at low invariant mass show in-medium effects like a collisional broadening of the vector…
The medium modification of vector meson properties and its effects on thermal photon and dilepton emission rates from hot/dense hadronic matter are discussed. The role of spectral changes of hadrons in explaining the WA98 photon data and…
In this work we analyse the theoretical uncertainties on the predictions for the photoproduction of light vector mesons in coherent pp, pA and AA collisions at the LHC energies using the color dipole approach. In particular, we present our…
Relativistic, kinematically complete phenomenological expressions for the dilepton decay rates of nucleon resonances with arbitrary spin and parity are derived in terms of the magnetic, electric, and Coulomb transition form factors. The…
Cherenkov gluons may be responsible for the asymmetry of dilepton mass spectra near rho-meson observed in experiment. They can be produced only in the low-mass wing of the resonance. Therefore the dilepton mass spectra are flattened there…
Theoretical and experimental studies of hot and/or dense matter, such as is created in high-energy heavy-ion collisions, and encountered in compact objects in astrophysics, constitute one of the most active frontiers in nuclear physics. In…
We establish the extent to which photons and dileptons are penetrating probes of hot hadronic matter by computing mean free paths. Absorption is indeed negligible for real photons as mean free paths are roughly tenths of \AAngstr\"oms.…
We study photoproduction of rho mesons in a model of hidden local symmetry. The rho meson is introduced as a hidden gauge boson and a phenomenological rho meson-nucleon Lagrangian is constructed respecting chiral symmetry. It is shown that…
Dileptons represent a unique probe for nuclear matter under extreme conditions reached in heavy-ion collisions. They allow to study meson properties, like mass and decay width, at various density and temperature regimes. Present days models…
We calculate the probability for dilepton production in central relativistic heavy ion collisions due to the gamma-gamma mechanism. This is a potential background to more interesting mechanisms. We find that this mechanism is negligible in…
We carry out a study of intermediate-mass (between 1 and 2.5 GeV) dilepton spectra from hadronic interactions in heavy-ion collisions. The processes considered are $\pi\pi\to l{\bar l}$, $\pi\rho\to l{\bar l}$, $\pi a_1\to l{\bar l}$,…
The vector channel spectral function and the dilepton production rate from a QCD plasma at a temperature above a few hundred MeV are evaluated up to next-to-leading order (NLO) including their dependence on a non-zero momentum with respect…
Inclusive non-diffractive photoproduction of rho(770)^0, K^*(892)^0 and phi(1020) mesons is investigated with the H1 detector in ep collisions at HERA. The corresponding average \gamma p centre-of-mass energy is 210 GeV. The mesons are…
We present data on dielectron emission in proton induced reactions on a Nb target at 3.5 GeV kinetic beam energy measured with HADES installed at GSI. The data represent the first high statistics measurement of proton-induced dielectron…
We discuss the elastic photo- and leptoproduction of rho^0-mesons from nucleons at Q^2 < 1 GeV^2 as studied in recent experiments at HERA and FNAL. We find that the mass distribution of the measured \pi^+\pi^- pairs is determined to a large…