Related papers: Dilepton Production and Chiral Symmetry
HADES is the only operating dielectron spectrometer in the energy regime 1-2 AGeV. The physics program aims at a systematic investigation of dielectron production in heavy ion as well as elementary and pion-induced reactions. This…
The neutral pion photoproduction on the proton near threshold has a very small scattering cross section when compared to the charged channels, which in ChPT is explained by strong cancellations between the lowest order pieces. Therefore it…
A survey is made of semileptonic and nonleptonic kaon decays in the framework of chiral perturbation theory. The emphasis is on what has been done rather than how it was done. The theoretical predictions are compared with available…
Using the latest quark Sivers functions extracted from the global analysis of available data on single transverse spin asymmetry (SSA), we calculate the SSA of Drell-Yan inclusive production of lepton pairs of invariant mass $Q$ at both…
We present a model of electron-positron pair production in pion-nucleon collisions in the exclusive reaction \pi N -> Ne^+e^-. The model is based on an effective field theory approach, incorporating 16 baryon resonances below 2 GeV.…
I report on recent progress in the study of mass generation in non-abelian gauge theories, and concentrate on the origin of constituent masses in QCD. I argue that a consistent formalism has been developed to describe chiral symmetry…
Employing thermal dilepton rates based on medium-modified electromagnetic correlation functions we show that recent dimuon spectra of the NA60 collaboration in central In-In collisions at the CERN-SPS can be understood in terms of radiation…
Two recent measurements by the D0 Collaboration of spin correlation in ttbar production using 5.4 fb^-1 of Tevatron ppbar collider data are presented. Both rely on the dilepton final state of ttbar. One measurement relies on full…
We study the Sivers asymmetry in inelastic $J/\psi$ leptoproduction, $ep^\uparrow \to e+ J/\psi+X$, within a transverse momentum dependent scheme, the so-called generalized parton model (GPM). The effects of final-state interactions are…
The masses of hadrons in the vacuum, where the chiral symmetry is restored, and in the medium are in general different even when the changes in the order parameters of chiral symmetry are the same. Here, we first discuss the relation…
Starting from a realistic one--boson--exchange--model fitted to the amplitudes of elastic nucleon--nucleon scattering and the process $NN\rightarrow N\Delta$ we perform a fully relativistic and gauge invariant calculation for the dilepton…
We study finite temperature effects on dilepton production from pion-pion annihilation in hot hadronic matter. The softening of the pion dispersion relation in a medium is found to enhance the production rate of dileptons with invariant…
In sqrt(sNN) = 200 GeV Au+Au collisions PHENIX reported a significant enhancement in the low-mass region (0.1 < m_ee < 0.7 GeV) of the dielectron spectrum, which is still not fully understood. Several theoretical works and an indirect…
In this short review the results of detailed studies for dilepton production from $p+A$ and $A+A$ reactions at SIS energies are presented. The calculations are based on a semi-classical BUU transport model that includes the off-shell…
Results of the computer simulation of dilepton production from the expanding pion gas created in ultrarelativistic Pb+Pb 160 GeV/n collisions are presented. Finite size of the expanding pion gas influences invariant mass spectrum of…
We report on recent progress on the chiral unitary approach, analogous to the effective range expansion in Quantum Mechanics, which is shown to have a much larger convergence radius than ordinary chiral perturbation theory, allowing one to…
Theoretical predictions for the production cross sections of leptoquarks at the CERN LHC are presented including higher-order QCD corrections. These corrections reduce the dependence on the renormalization/factorization scales…
It has recently been suggested that the observed structure of parity doublets, seen in the spectrum of highly excited baryons, may be due to the effective restoration of chiral symmetry for these states. This chiral symmetry restoration…
A unique parameterization of secondary (thermal) dilepton and photon yields in heavy-ion experiments at CERN-SPS is proposed. Adding those thermal yields to background contributions the spectral shapes of the CERES/NA45, NA38, NA50,…
We review the relationship between the pion decay constant $f_\pi$, the chiral symmetry restoration temperature $T_c$ and the phenomenology of low energy chiral symmetry breaking in view of the recent confirmation of the existence of a…