LHC能量下D介子的核修正因子

The Nuclear Modification Factor for D Meson at LHC Energies

高能质子-质子(p-p)和质子-原子核(p-A)碰撞过程中产生的D介子是分析碰撞后生成的饱和胶子性质的重要途经。考虑领头阶下的强耦合效应,在色玻璃凝聚理论(CGC)框架下研究了LHC(Large Hadron Collider,LHC)能量下p-p(p-A)碰撞过程中的D介子产生。采用由KLR-AdS/CFT色偶极模型通过傅里叶变换得到的偶极关联因子,同时利用Glauber模型考虑冷核物质效应,计算了质心能量为5.02 TeV时质子-铅核(p-Pb)碰撞中不同碰撞中心度下D介子的产生截面,并在此基础上研究了p-Pb碰撞中D介子产生及其半轻子衰变过程中的核修正因子。通过与大型强子对撞机(LHC)实验结果比较发现:考虑强耦合效应后的理论结果与ALICE和LHCb合作组的最新实验数据符合得更好。最后,本文对LHC碰撞质心能量为8.16 TeV时p-Pb碰撞中D介子产生的核修正因子给出了理论预言,结果显示此能量下核修正因子理论值比5.02 TeV时略大。

The D-meson production in high energy proton-proton(p-p)and proton-nucleus(p-A)collisions is an important approach to study the character of saturation gluon.By considering the strong coupling effects at leading order,the D meson production in high energy p-p and p-A collisions at LHC energies is studied in the framework of Color Glass Condensate(CGC).Using the dipole amplitude obtained from the KLR-AdS/CFT color dipole model through Fourier transform,and taking into account the cold nuclear matter effects,we investigate the D meson cross section in proton-lead(p-Pb)collisions at■=5.02 TeV in different centrality class.Then,we calculate the nuclear modification factor for D meson production and semi-leptonic decay processes in p-Pb collisions at■=8.16 TeV.It is found that the theoretical results considered the strong coupling effects fit better with the latest experimental data from ALICE and LHCb Collaboration than those obtained without considering the strong coupling effects.Finally,we also predict the results for the experiments at■=8.16 TeV of the Large Hadron Collider(LHC).It is shown that the theoretical results at■=8.16 TeV are larger than those results at■=5.02 TeV.