Production Of Heavy Quark And Energy Loss Of Charm Quark Via Dimuon Production In ALICE

Lattice QCD calculations predict a phase transition from hadronic matter to a de-confined, locally thermalized Quark-Gluon Plasma (QGP) state at high temperature and small baryon density. High Energy Heavy Ion Collision experiments can severed as a good tool to study QGP. Charm and bottom quarks are mostly produced in the early time of the collision and can be better predicted by pQCD as their large masses, so they can severed as a promising tool to test the coherence of the interpretation of nuclear shadowing and quenching effects as energy loss in a deconfined medium.At Relativistic Heavy Ion Collider (RHIC), a phenomenon that light hadrons at high transverse momentum are strongly suppressed in nucleus-nucleus collisions compared to those in p+p and d+Au collisions has been observed and explained as a confirmation of jet quenching, which is due to energy loss suffered by hard par-tons when they traverse the medium formed in ultra-relativistic heavy ion collisions. And due to dead cone effect heavy quark should lose much less energy compared to light partons. However, a significant suppression of electrons from heavy quarks in mid-rapidity region at high pt has been observed in central Au+Au collision at RHIC, indicating substantial energy loss of heavy quark, although the statistics is limited. At Large Hadron Collider (LHC), it is supposed that heavy flavors will be abundantly produced. This will offer a good opportunity to characterize the medium formed in the collisions as heavy quarks are mainly produced by hard processes at the very beginning of the collisions. Since heavy quark decays will dominate the lepton pair continuum between J/ψ and Z~0 peaks, the lepton pair spectra are expected to provide valuable information on the energy loss of heavy quarks. Currently there are different scenarios on the energy loss of heavy quarks, among which a quenching weight approach based on BDMPS formalism describes light hadron spectra well and fits relatively good to the spectra of electrons from heavy flavors measured at mid-rapidity. It thus would be interesting to apply the approach to the forward region toexplore the energy loss effect on muon spectra.Based on the HVQMNR model on heavy flavor production and the BDMPS approach on parton energy loss, we study yields of heavy quarks in LHC energies and the energy loss effect of charm quarks on dimuon yields in Pb-Pb collisions in the forward rapidity region 2.5 < r) < 4 covered by ALICE Forward Muon Spectrometer at v^iiw = 5.5 TeV. Firstly, by introducing nuclear shadowing effect to HVQMNR model, which presents a fully exclusive partonic differential cross section calculation including all the relevant partonic subprocesses, we calculate the average heavy quark yields produced per nucleon-nucleon collision in nucleus-nucleus collisions. Then we extrapolate the results to nucleus-nucleus collisions using the Glauber model. To study the effect of charm quark energy loss on dimuon production, we sample the energy loss according to quenching weight. Finally, the dependence of dimuon spectra within the acceptance of ALICE Forward Muon Spectrometer on energy loss of charm quark is investigated by varying the transport coefficient. Results show that (di)muon spectra are very sensitive to the charm quark energy loss and can provide valuable information on the energy loss of heavy flavors.