Dilepton spectra from expanding hot quark matter

Suppression of Dilepton in Expanding Hot Baryon-Rich Quark-Gluon Matter

“…~ Giving the initial temperature and the initial baryon distributions of the fireball as seen in Ref. 5, we have obtained the baryon and temperature distributions via solving CRHE (3) in the phase diagram. With the help of the relation between baryon density and chemical potential of quark1, we, in turn, obtain chemical potentials pq and -pq of the quark and anti-quark, subsequently, distribution functions fq(k) and f q ( k ) of the quark and anti-quark.…”

Dilepton distribution for the baryon-rich quark - gluon fireball

“…In this work, we study the dilepton production of an expanding hot baryon-rich QGM on the basis of the relativistic hydrodynamic model. In order to include the effect of the 0954-3899/96/121751+08$19.50 c 1996 IOP Publishing Ltd particle distribution on the production, first, for the quark phase, dileptons produced from qq annihilations are calculated as has been done in [10,17], where the rate is obtained by the Fermi-Dirac distribution function; for the hadronic phase, taking into account the pion dispersion relation as in [18], we calculate dileptons predominantly produced from ππ annihilations using the rate expression derived from a momentum distribution of particles, which depends on both the temperature and the particle density [19,20]. Then, with the help of the equation of state of the system, we solve the generalized relativistic hydrodynamic equations (RHE) including the equation of baryon number conservation in the phase diagram to obtain both the temperature and the quark chemical potential distribution in spacetime, which are used to calculate the production rate.…”

“…In [19] Zejun et al have indicated that one cannot study the influence of the particle distribution on production via the momentum distrbution of particles f (p) = exp(−E/T ), where E is the particle energy.…”

“…From this we have obtained the dilepton production spectrum dN/ d 4 X dM by an appropriate change of variables. For the hadronic phase, the dilepton production spectrum is calculated as in [18][19][20] using the following momentum distribution of particles [21],…”

“…The system considered in this paper evolves very differently from those in [2,6,19]. Since here both the temperature and the quark chemical potential are functions of spacetime, it necessarily takes a long time for values (µ q , T ) of various local regions of the baryonrich QG system to reach different points of the phase boundary at different times to make local phase transitions.…”