论文标题
w $^\ pm $ -boson在p $ - $ pb碰撞中的生产$ \ sqrt {s_ {nn}} = 8.16 $ \ sqrt {s_ {s_ {nn}} = 5.02 $ tev $ tev和pbpb碰撞
W$^\pm$-boson production in p$-$Pb collisions at $\sqrt{s_{NN}} = 8.16$ TeV and PbPb collisions at $\sqrt{s_{NN}} = 5.02$ TeV
论文作者
论文摘要
以p $ - $ pb碰撞测量的w $^\ pm $玻色子的产生，每核$ - $ nucleon碰撞$ \ sqrt {s_ {s_ {nn}} = 8.16 $ tev and pb $ - $ - $ - $ - $ - $ - $ pb碰撞在$ \ sqrt at in nnn} ande}提出。 W $^\ PM $玻色子是通过其Muonic衰减通道测量的，Muon在伪型区域中重建了$ -4 <η^μ_ {\ rm lab} <-2.5 $，带有横向动量$ p _ {\ rm t}^μ> 10 $> 10 $ gev/$ c $。 While in Pb$-$Pb collisions the measurements are performed in the forward ($2.5 < y^μ_{\rm cms} < 4$) rapidity region, in p$-$Pb collisions, where the centre-of-mass frame is boosted with respect to the laboratory frame, the measurements are performed in the backward ($-4.46 < y^μ_{\rm cms} < -2.96 $）和向前（$ 2.03 <y^μ_ {\ rm cms} <3.53 $）速度区域。 W $^{ - } $和W $^{+} $生产横截面，Lepton-Charge不对称和核修饰因子是根据MUON快速性的函数评估的。为了研究生产作为p $ - $ pb碰撞中心性的函数，将W $^{ - } $和w $^{+} $玻色子的生产交叉部分组合在一起，并标准化为二进制核素$ - $ $ nucleon $ - $ nucleon collision $ \ langle n_ \ langle n_ \ mathrm {coll collm {在PB $ - $ PB碰撞中，同样的测量结果是碰撞中心性的函数。还报道了w $^\ pm $ -boson交叉部分在p $ - $ pb和pb $ - $ pb碰撞的研究。将结果与扰动QCD（PQCD）计算进行了比较，有和没有Parton分布函数（PDFS）的核修改以及LHC的可用数据。在两个碰撞系统中发现了与理论期望的显着偏差，这表明测量值可以为确定核PDF（NPDF），尤其是光夸克分布提供其他约束。
The production of the W$^\pm$ bosons measured in p$-$Pb collisions at a centre-of-mass energy per nucleon$-$nucleon collision $\sqrt{s_{NN}} = 8.16$ TeV and Pb$-$Pb collisions at $\sqrt{s_{NN}} = 5.02$ TeV with ALICE at the LHC is presented. The W$^\pm$ bosons are measured via their muonic decay channel, with the muon reconstructed in the pseudorapidity region $-4 < η^μ_{\rm lab} < -2.5$ with transverse momentum $p_{\rm T}^μ> 10$ GeV/$c$. While in Pb$-$Pb collisions the measurements are performed in the forward ($2.5 < y^μ_{\rm cms} < 4$) rapidity region, in p$-$Pb collisions, where the centre-of-mass frame is boosted with respect to the laboratory frame, the measurements are performed in the backward ($-4.46 < y^μ_{\rm cms} < -2.96$) and forward ($2.03 < y^μ_{\rm cms} < 3.53$) rapidity regions. The W$^{-}$ and W$^{+}$ production cross sections, lepton-charge asymmetry, and nuclear modification factors are evaluated as a function of the muon rapidity. In order to study the production as a function of the p$-$Pb collision centrality, the production cross sections of the W$^{-}$ and W$^{+}$ bosons are combined and normalised to the average number of binary nucleon$-$nucleon collision $\langle N_\mathrm{coll} \rangle$. In Pb$-$Pb collisions, the same measurements are presented as a function of the collision centrality. Study of the binary scaling of the W$^\pm$-boson cross sections in p$-$Pb and Pb$-$Pb collisions is also reported. The results are compared with perturbative QCD (pQCD) calculations, with and without nuclear modifications of the Parton Distribution Functions (PDFs), as well as with available data at the LHC. Significant deviations from the theory expectations are found in the two collision systems, indicating that the measurements can provide additional constraints for the determination of nuclear PDF (nPDFs) and in particular of the light-quark distributions.
