Drell-Yan nuclear modification due to nuclear effects of nPDFs and initial-state parton energy loss

• 作者: Li-Hua Song Peng-Qi Wang Yin-Jie Zhang
• 来源期刊: 中国物理C（英文版）
• 年，卷（期）: 2021,（4）
• 所属期刊栏目: LETTER
• 页码范围: 33-40
• 页数: 8页
• 语种: 英文
• DOI: 10.1088/1674-1137/abe110

摘要

By globally analyzing nuclear Drell-Yan data including all incident energies,the nuclear effects of nuclear parton distribution functions (nPDFs) and initial-state parton energy loss are investigated.Based on the LandauPomeranchuk-Migdal (LPM) regime,the calculations are carried out by means of analytic parametrizations of quenching weights derived from the Baier-Dokshitzer-Mueller-Peigné-Schiff (BDMPS) formalism and using the new EPPS 16 nPDFs.It is found that the results are in good agreement with the data and the role of the energy loss effect in the suppression of Drell-Yan ratios is prominent,especially for low-mass Drell-Yan measurements.The nuclear effects of nPDFs become more obvious with increasing nuclear mass number A,the same as the energy loss effect.By a global fit,the transport coefficient extracted is (q) =0.26 ± 0.04 GeV2/fm.In addition,to avoid diminishing the QCD NLO correction to the data form of Drell-Yan ratios,separate calculations of the Compton differential cross section ratios RFe(W)/C(xr) at 120 GeV are performed,which provides a feasible way to better distinguish the gluon energy loss in Compton scattering.It is found that the role of the initial-state gluon energy loss in the suppression of Compton scattering ratios is not very important and disappears with the increase of xF.