Related papers: Medium effects on meson couplings and dilepton spe…
Kaon in-medium masses and mean-field potentials are calculated in isotopically symmetric pion matter to one loop of chiral perturbation theory. The results are extended to RHIC temperatures using experimental data on $\pi K$ scattering…
The enhancement in the dilepton spectrum observed in heavy-ion collisions for invariant electron-positron masses in the range 0.15 GeV/c$^2 < M_{e^+e^-} <$ 0.6 GeV/c$^2$ has recently been traced back to a corresponding enhancement in $pn$…
It is known that the decay process \eta\rightarrow\pi^0\pi^+\pi^- in free space is possible due to the isospin-symmetry breaking in Quantum Chromodynamics (QCD), i.e., the small mass difference between u and d quarks: The small width is…
The medium modification of vector meson properties in hot/dense hadronic matter and its role in explaining the CERES/NA45 dilepton data at different centralities are discussed.
The interference of the $\rho^0$ and $\omega$ mesons has been studied in the hadronic and leptonic decay channels, i.e., dipion and dilepton decay channels respectively, but this interference is not studied yet in the semihadronic or…
Dilepton production from resonance scattering in hot hadronic matter is studied. Including the widths of these resonances, which enhance the phase space for dilepton production, we find that the production rate is significantly increased if…
We report on a self-consistent calculation of the in-medium spectral functions of the rho and omega mesons at finite baryon density. The corresponding in-medium dilepton spectrum is generated and compared with HADES data. We find that an…
We explore how the $\eta$-$\pi^0$ mixing angle and the $\eta$ meson decay into $\pi^{+}\pi^{-}\pi^0$ and 3$\pi^{0}$ are modified in the nuclear medium on the basis of the in-medium chiral effective theory with the isospin asymmetry $\alpha$…
In case of an UA(1) symmetry restoration in a hot and dense hadronic matter, the mass of the produced hadrons and mesons can significantly change, and their production cross-section can also be modified. In this M.Sc. Thesis I search for…
There exist model calculations showing the modification of the hadronic parameters of $\rho$ meson in the nuclear environment. From these parameters, we extract the $\rho$ meson nucleus optical potential and show the medium effect due to…
The invariant mass spectrum of the $e^{+}e^{-}$ and $\mu ^{+}\mu ^{-}$ pairs from decays of light unflavored mesons with masses below the $\phi (1020)$-meson mass to final states containing along with a dilepton pair one photon, one meson,…
Dilepton and photon production in heavy-ion collisions at SPS energies is studied in the relativistic transport model that incorporates self-consistently the change of hadron masses in dense matter. It is found that the dilepton spectra in…
We present a unified description of the vector meson and dilepton production in elementary and in heavy ion reactions. The production of vector mesons ($\rho,\omega$) is described via the excitation of nuclear resonances ($R$). The…
We summarize the current theoretical and experimental status of the spectral changes of vector mesons ($\rho$, $\omega$, $\phi$) in nuclear medium. Various approaches including QCD sum rules, effective theory of hadrons and bag models show…
Based on an effective Lagrangian which combines chiral SU(3) dynamics with vector meson dominance, we have developed a model for the forward vector meson-nucleon scattering amplitudes. We use this as an input to calculate the low energy…
We discuss the similarities and differences for the theories of Rapp, Wambach and collaborators (called R/W in short) and those based on Brown-Rho scaling (called B/R), as applied to reproduce the dileptons measured by the CERES…
The mass shift $\Delta m_{\rho}$ and width broadening $\Delta\Gamma_{\rho}$ of $\rho$ mesons produced in heavy ion collisions is estimated using a general formula which relates the in-medium mass shift of a particle to the real part of the…
Vector mesons containing light quarks are thought to have their masses reduced in dense nuclear matter, sacrificing some of their energy to the scalar field which becomes appreciable at finite baryon density. Model calculations find masses…
The in-medium properties of the vector mesons are known to be modified significantly in hot and dense hadronic matter due to vacuum polarisation effects from the baryon sector in the Walecka model. The vector meson mass drops significantly…
The excess of low invariant mass dilepton yield in heavy ion collisions arising from reduction in the rho meson mass at finite temperatures is partially suppressed because of the effect on the width of the rho meson induced by Bose…