TY  - JOUR
A1  - Endres, Stephan
A1  - Hees, Hendrik van
A1  - Weil, Janus
A1  - Bleicher, Marcus
T1  - Vector meson spectral functions in a coarse-graining approach
T2  - EPJ Web of Conferences
N2  - Dilepton production in heavy-ion collisions at top SPS energy is investigated within a coarse-graining approach that combines an underlying microscopic evolution of the nuclear reaction with the application of medium-modified spectral functions. Extracting local energy and baryon density for a grid of small space-time cells and going to each cell’s rest frame enables to determine local temperature and chemical potential by application of an equation of state. This allows for the calculation of thermal dilepton emission. We apply and compare two different spectral functions for the ρ: A hadronic many-body calculation and an approach that uses empirical scattering amplitudes. Quantitatively good agreement of the model calculations with the data from the NA60 collaboration is achieved for both spectral functions, but in detail the hadronic many-body approach leads to a better description, especially of the broadening around the pole mass of the ρ and for the low-mass excess. We further show that the presence of a pion chemical potential significantly influences the dilepton yield.
Y1  - 2015
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/71923
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-719234
SN  - 2100-014X
VL  - 97
IS  - 00014
PB  - EDP Sciences
CY  - Les Ulis
ER  -