Related papers: Energy weighted sum rules for mesons in hot and de…
The properties of vector mesons in nuclear matter are discussed. Results for the momentum dependence of the $\rho$-meson self energy in matter due to $\rho N$ interactions are presented, and consequences for the production rate of $e^+e^-$…
We summarize the current theoretical and experimental status of the spectral changes of vector mesons ($\rho$, $\omega$, $\phi$) at finite baryon density. Various approaches including QCD sum rules, effective theory of hadrons and bag…
We present a lattice QCD calculation of the ground-state energy shifts of various baryons in a medium of pions or kaons at a single value of the quark mass corresponding to a pion mass of m_\pi~390 MeV and a kaon mass of m_K~540 MeV, and in…
The thermal properties of $f_{2}(1270)$, $a_{2}(1320)$ and $K_2^*(1430)$ light tensor mesons are investigated in the framework of QCD sum rules at finite temperature. In particular, the masses and decay constants of the light tensor mesons…
Mass shifts $\Delta m$ of particles in nuclear matter relative to their vacuum values are considered. A general formula relating $\Delta m(E)$ ($E$ is the particle energy) to the real part of the forward particle-nucleon scattering…
The validity of Weinberg's two sum rules for massless QCD, as well as the six additional sum rules introduced into chiral perturbation theory by Gasser and Leutwyler, are investigated for the extended Nambu-Jona-Lasinio chiral model that…
Recently we have developed a novel chiral power counting scheme for an effective field theory of nuclear matter with nucleons and pions as degrees of freedom [1]. It allows for a systematic expansion taking into account both local as well…
The electromagnetic emission rates at SPS energies satisfy spectral constraints in leading order in the pion and nucleon densities. These constraints follow from the strictures of broken chiral symmetry. We saturate these constraints using…
The production of pions and kaons has been measured in Au+Au collisions at beam energies from 0.6 to 1.5 AGeV with the Kaon Spectrometer at SIS/GSI. The K+ meson multiplicity per nucleon is enhanced in Au+Au collisions by factors up to 6…
Sum rules originally derived for the M\"ossbauer Effect are applied to weak semileptonic B decays. The sum rules follow from assuming that the decay by electroweak boson emission of an unstable nucleus or heavy quark in a bound system is…
We calculate the vector and axial-vector form factors of $B_{u,d,s}$ decays into P-wave axial-vector mesons in the light-cone sum rule approach. For the sum rule results, we have included corrections of order $m_A/m_b$, where $m_A$ is the…
The strong coupling constant of doubly heavy baryons with light pseudoscalar mesons $ \pi $ and $ K $ are computed within the light cone sum rules. We take into account two-particle and three-particle distribution amplitudes of the said…
We derive the equation of state of nuclear matter including vacuum polarization effects arising from the nucleons and the sigma mesons in the quark-meson coupling model which incorporates explicitly quark degrees of freedom with quark…
A fit of the experimental data to the total cross section of the process $\gamma\gamma->\pi^+\pi^-$ in the energy region from threshold to 2500 MeV has been carried out using dispersion relations with subtractions for the invariant…
We investigate the behavior of the one body propagator in SQED. The self energy is calculated using three different methods: i) the simple bubble summation, ii) the Dyson-Schwinger equation, and iii) the Feynman-Schwinger represantation.…
For a $Q \cdot Q$ interaction the energy weighted sum rule for isovector orbital magnetic dipole transitions is proportional to the difference $\sum B(E2, isoscalar) - \sum B(E2, isovector)$, not just to $\sum B(E2, physical)$. This fact is…
Based on a recent meson-exchange model for the vacuum $\pi\pi$ interaction we compute selfconsistently the in-medium $\pi\pi$ scattering amplitude and pion selfenergy in a hot $\pi N\Delta$ gas. The contributions to the pion selfenergy are…
The work presented at this workshop is divided into two parts. In the first part, the mass and decay width of the $\phi$-meson in cold nuclear matter are computed in an effective Lagrangian approach. The medium dependence of these…
The properties of mesonic resonances can be calculated in terms of the low-energy coefficients of chiral perturbation theory (chiPT) by extending unitarized chiPT to higher energies. On the other hand these low-energy coefficients can be…
Particle-hole modes with quantum numbers of pions and negative kaons can propagate in nuclear matter. We discuss possible manifestations of these modes in experiments on heavy-ion collisions and on neutrino-nucleus scattering. Calculations…