B. Kampfer et al., RAPIDITY DEPENDENCE OF THERMAL DILEPTONS RESULTING FROM HADRONIZING QUARK-GLUON MATTER WITH FINITE BARYON CHARGE, ZEITSCHRIFT FUR PHYSIK A-HADRONS AND NUCLEI, 353(1), 1995, pp. 71-77
The influence of a non-vanishing baryon charge on the rapidity distrib
ution of dileptons produced in ultrarelativistic heavy-ion collisions
is studied. We employ a frozen motion model with scaling invariant exp
ansion of the hadronizing quark-gluon plasma as well as a realistic ra
pidity distribution of secondary particles (i.e., pions and baryons) e
xpected for RHIC energies. We demonstrate a sizeable suppression of th
e thermal dilepton yield at large rapidities due to the finite baryon
density. This affects the most favorable rapidity window for using dil
eptons for the diagnostic of the quark-gluon plasma and the early temp
erature distribution of the hot reaction zone. To discriminate the the
rmal dileptons from Drell-Yan background we propose to utilize the dil
epton yield scaled suitably by the pion multiplicity as function of ra
pidity.