夸克胶子等离子体（QGP）是以解囚禁的夸克和胶子为基本组分的新物质形态。高能重离子碰撞实验的重要目标是产生QGP并定量研究其性质。各种实验探针除了对QGP产生的热核物质效应敏感外，还会受到与QGP产生无关的冷核物质（CNM）效应的影响。质子-重核碰撞因时空尺度小，不能产生QGP，对这一碰撞中相关实验探针进行精确测量可对核部分子分布函数（nPDF）和色玻璃凝聚（CGC）等CNM效应进行有效限定，为重离子碰撞中研究QGP特性提供参考。粲夸克因质量较大，只能在重离子碰撞的早期通过硬散射成对产生，在强子化之前会经历火球的整个演化过程，是QGP的有效探针。目前RHIC和LHC的重离子碰撞中对粲强子核修正因子测量发现了粲夸克在QGP介质中的较大能损，对Ds+和D0粒子比的测量也发现了奇异性产额增强。但nPDF和 CGC等冷核物质效应也会造成粲强子核修正因子的压低，质子重核等小碰撞系统中也存在奇异性增强。目前需要在质子重核碰撞中对相应粲强子观测量进行精确测量限定这些粲强子探针中的CNM效应。大型强子对撞机LHC上的LHCb探测器于2013年初采集了积分亮度为1.58nb?1，核子核子质心系能量为5.02TeV的质子铅核(pPb)对撞数据。本论文利用这些数据首次测量了pPb对撞中前向瞬D+和Ds+的微分截面，运动学区间覆盖前向快度区1.5
Quark-gluon plasma (QGP) is a new state of matter with deconfined quarks and gluons as fundamental constituents. An essential goal of high-energy heavy-ion collision experiments is to create QGP and investigate its properties quantitatively. Various experimental probes, which are sensitive to the hot nuclear matter effects induced by QGP, may also be affected by the cold nuclear matter (CNM) effects irrelevant to the QGP formation. Precise measurements of these experimental probes in proton-nucleus collisions, which cannot produce QGP due to their small time-space scales, can effectively quantify the CNM effects such as nuclear parton distribution function (nPDF) and color glass condensate (CGC), and provide a reference for the study of QGP properties in heavy-ion collisions.Due to their large mass, charm quarks are pair-produced in the early stage of heavy-ion collisions by hard scatterings and will undergo the whole evolution of the fireball before hadronization, and are sensitive probes to the QGP medium properties. The present measurements on charm hadron nuclear modification factors in heavy-ion collisions at RHIC and LHC reveal a large energy loss of charm quarks in the QGP medium, and the measurement of ?+𝑠 to ?0 yield ratios also exhibits the effect of enhanced strangeness production in charm hadronization. However, cold nuclear matter effects such as nPDF and CGC may also suppress the charm hadron nuclear modification factor, and the strangeness enhancement also exists in small collision systems such as proton-nucleus. Currently, the precisemeasurements of these charm hadron observables in proton-nucleus collisions become essential to constrain the CNM effects in these QGP probes.In early 2013, the LHCb detector at the Large Hadron Collider (LHC) has collected the data of proton-lead (?Pb) collisions with an integrated luminosity of 1.58±0.02 nb?1at nucleon-nucleon centre-of-mass energy of √?NN = 5.02 TeV. This thesis utilizes these data to measure for the first time the differential cross-sections of prompt ?+ and 𝐷?+ in 𝑝Pb collisions at forward region, with the measured kinematic intervals covering the forward rapidity region of 1.5 < ? < 4.0 and the backward rapidity region of -5.0 < ? < -2.5 and the transverse momentum range of 0 < ?T < 14 GeV/?. Using these cross-section results, this thesis calculates the nuclear modification factor ?𝑝Pb and the forward-backward cross-section ratio ?FB for both particles. CNM effects that influence the production of charm hadrons are studied. The cross-section ratios between ?+𝑠, ?+ and 𝐷0 are also measured in this thesis to explore the charm quark hadronization mechanism and strangeness enhancement in ?Pb collisions.The ?𝑝Pb and ?FB measurements indicate significant CNM effects in ?Pb collisions at 5.02 TeV. The cross-sections of both ?+ and 𝐷+? are obviously suppressed in the forward rapidity region, which are in good agreement with the previous ?0 measurements and the theoretical predictions of nPDF and CGC within uncertainties, indicating the existence of nuclear shadowing effects in the small momentum fraction ?. In the backward rapidity region, the suppression of ?𝑠+ production is insignificant and in good agreement with the nPDF calculations, suggesting the existence of nuclear anti-shadowing effects, while ?+’s 𝑅?Pb are slightly smaller than the nPDF predictions. In particular, ?+’s 𝑅FB at high transverse momentum are significantly larger than the nPDF calculations, implying the possible existence of other nuclear matter effects in ?Pb collisions. The cross-section ratios ?𝐷+/?0, 𝑅?+𝑠 /?0 and 𝑅?𝑠+/?+ demonstrate a small suppression of the ?+ cross-section relative to ?0 and 𝐷+? in the backward rapidity region, but no evidence of ?𝑠+ enhancement relative to ?0 production is observed in both forward and backward rapidities.
