相关论文: Hadrons in Medium - Observables
Detailed predictions for dilepton production from $p A$ reactions at SIS energies are presented within a semi-classical BUU transport model that includes the off-shell propagation of vector mesons nonperturbatively and calculates the width…
In this talk I first discuss predictions based on QCD sum rules and on hadronic models for the properties of vector mesons in the nuclear medium. I then describe possible experimental signatures and show detailed predictions for dilepton…
Using the transport model, we have studied dilepton production from heavy-ion collisions at Bevalac energies. It is found that the enhanced production of low-mass dileptons observed in the experiment by the DLS collaboration cannot be…
The properties of strange hadrons, i.e. of kaons and hyperons, in the nuclear medium are discussed in connection with neutron star properties and relativistic heavy-ion collisions. Firstly, the relevant medium modifications of a kaon in a…
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…
It is investigated under which conditions an adiabatic adaption of the dynamic and spectral information of vector mesons to the changing medium in heavy ion collisions, as assumed in schematic model calculations and microscopic transport…
We will summarize the progress in understanding the changes in the vector meson spectral density in nuclear medium using the constraint equations obtained from the Borel transformed dispersion relation and QCD Operator Product Expansion. We…
A significant drop of the vector meson masses in nuclear matter is observed in a chiral SU(3) model due to the effects of the baryon Dirac sea. This is taken into account through the summation of baryonic tadpole diagrams in the…
We present dilepton spectra from p+p, d+p and p+Nb reactions at SIS energies, which were simulated with the GiBUU transport model in a resonance model approach. These spectra are compared to the data published by the HADES and DLS…
A recently developed model for $\rho$-meson propagation in dense hadronic matter is applied to total photoabsorption cross sections in $\gamma$-proton and $\gamma$-nucleus reactions. Within the vector dominance model the photon coupling to…
The modifications of hadronic masses and decay widths at finite temperature and baryon density are investigated using a phenomenological model of hadronic interactions in the Relativistic Hartree Approximation. We consider an exhaustive set…
The first direct measurement of the dependence on target nuclear mass of the average squared transverse momentum <pt**2> of pi+, pi-, and K+ mesons from deep-inelastic lepton scattering is obtained as a function of several kinematic…
Theoretical approaches to assess modifications of vector mesons in the medium, as well as their experimental identification via electromagnetic probes, are discussed. Implications for the nature of chiral symmetry restoration in hot/dense…
We estimate the numbers and mass spectra of observed lepton and kaon pairs produced from $\phi$ meson decays in the central rapidity region of an Au+Au collision at lab energy 11.6 GeV/nucleon. The following effects are considered: possible…
Using a self-consistent quark model for nuclear matter we investigate variations of the masses of the non-strange vector mesons, the hyperons and the nucleon in dense nuclear matter (up to four times the normal nuclear density). We find…
We give a brief survey of theoretical evaluations of light vector mesons in hadronic matter, focusing on results from hadronic many-body theory. We emphasize the importance of imposing model constraints in obtaining reliable results for the…
Within a transport code simulation for heavy-ion collisions at bombarding energies around 1 AGeV, we demonstrate that double-differential di-electron spectra with suitable kinematical cuts are useful to isolate (i) the $\rho$ meson peak…
The hadron spectrum at finite density is an important observable for exploring the origin of hadron masses. In the KEK-PS E325 experiment, the di-electron decays of phi mesons inside and outside nuclei were measured using 12 GeV pA…
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…
Medium modification of dihadron fragmentation functions due to gluon bremsstrahlung induced by multiple partonic scattering is studied in both deep-inelastic scattering (DIS) off large nuclei and high-energy heavy-ion collisions within the…