Cold Nuclear Matter Effects Of Z Production In Heavy-ion Collisions At LHC

In the high energy nuclelear collisions,such as Lead-Lead collision at LHC,it will produce a cluster of extremely high energu and high density matter where quarks and gluons get deconfined and become asymptotically free. It is a new state of matter which is called quark-gluon plasma. Through the relativistic heavy ion collision experiments,we can study the property of the QGP.For the formation of QGP, there will be hot nuclear matter efects on the prodyction of final state particles in relativistic heavy ion collisions.but the cold nuclear matter effects will also affect the production of final state particles.Thus,studying the cold nuclear matter effects becomes very important for investigating the property of quark—gluon plasma.This thesis mainly investigates the cold nuclear matter effects on the Z boson production in relativistic heavy ion collisions.First we discuss the theoretical cal-culation of the LO cross section of Z0 production in proton proton collisions,and calculate the NLO differential cross section of Z0 production in dependence of rapid-ity in p+p collisions at 7.0 TeV with pQCD theory,utilizing the MCFM simulation and compare it with the CMS data；Furthermore,we calculate the differential cross section of Z0 production in dependence of rapidity and transverse momentum in P-b+Pb collisions at 2.76TeV and get the rapidity and transverse momentum spectrum of the nuclear modification factor,where we use the EPS09 parameterizing sets of nuclear parton distribution functions(nPDFs)to incorporate the normal cold nuclear matter matter effect, and find that due to anti-shadowing effect,the yields of Z pro-duction are enhanced at 10-100GeV of PT and in the central rapidity region｜yZ｜<1, but in the larger rapidity region 1<｜yZ｜<2,there will be a suppression due to shadowing effects and EMC effects；we also calculate the differential cross section of Z0 production in p+pb collision at 5.02TeV in dependence of rapidity and transverse momentum,then get the rapidity and transverse momentum spectrum of the nuclear modification factor,and find that there will be an enhancement at 10-100GeV of PT ,at 100GeV,the enhancement is about 4 percent,due to anti-shadowing effects and an enhancement also appears in the backward rapidity region due to anti-shadowing effects,but in the forward rapidity,there will be a suppression due to shadowing effects.After including the normal cold nuclear matter effects,we also try to study the initial state energy loss effects to the Z0 production through the simulation of the experiment p-Pb collision at 5.02TeV and Pb-Pb collision at 2.76TeV,and we find that the initial state energy loss effect is negligible for the large energy of the center mass frame.