大型强子对撞机（LHC）上采用一般质量变量味数方案的W玻色子与粲强子的伴随产生
Simultaneous production of a $W$ boson and a charmed hadron at the LHC in general-mass variable-flavour-number scheme
浏览论文内容
中文总结 AI 辅助
该研究在次领头阶量子色动力学下采用一般质量变量味数方案，分析LHC上W玻色子与粲强子的伴随产生，发现CT18A与ATLAS数据吻合最佳，还探讨了质子-铅碰撞中测量该过程的可能性。
中文摘要 AI 辅助
质子-质子碰撞中W±玻色子与粲强子的伴随产生为约束奇异夸克部分子分布函数（PDFs）提供了潜在探针。我们在微扰量子色动力学的次领头阶下，采用一般质量变量味数方案研究这些过程。通过考虑带相反电荷介子的截面比值，与非物理标度选择和碎裂函数相关的不确定性被有效抵消，使得PDFs带来的不确定性成为主导。将我们的计算结果与CT18A、MSHT20和NNPDF4.0这三种PDF以及ATLAS在质心系能量√s=13 TeV下的最新测量结果对比后发现，施加零奇异不对称性的CT18A与数据吻合最佳，而允许非零奇异不对称性的MSHT20和NNPDF4.0则与ATLAS数据存在较大张力。通过PDF重加权方法进一步确认了对奇异不对称性的敏感性。我们还研究了质子内可能存在的内粲夸克含量的影响，发现其无显著敏感性。最后，我们探索了在质子-铅碰撞中测量这些过程的可能性，结合高亮度LHC的预计探测器效率和积分亮度，这些过程应可被观测，但对核PDFs的约束能力相当有限。
英文摘要
The simultaneous production of a $W^\pm$ boson and a charmed hadron in proton-proton collisions offers a potential probe for constraining the strange quark parton distribution functions (PDFs). We study these processes at next-to-leading order in perturbative Quantum Chromodynamics within the general-mass variable-flavor-number scheme. By considering ratios of cross-section between oppositely charged mesons, uncertainties associated with unphysical scale choices and fragmentation functions are shown to effectively cancel out, leaving the uncertainty originating from the PDFs as the dominant one. By comparing our calculations with CT18A, MSHT20 and NNPDF4.0 PDFs with the recent ATLAS measurement at $\sqrt{s} = 13\,{\rm TeV}$ we find that CT18A, which imposes zero strangeness asymmetry, agrees best with the data, while MSHT20 and NNPDF4.0, both of which allow for a non-zero strangeness asymmetry, exhibit greater tension with the ATLAS data. The sensitivity to the strangeness asymmetry is further confirmed by the PDF reweighting methods. We also study the impact of possible intrinsic charm content of the proton finding no significant sensitivity. Finally, we explore the possibility of measuring these processes in proton-lead collisions. With the estimated detector efficiencies and projected luminositites at the high-luminosity LHC, these processes should be visible, yet with a rather limited constraining power for nuclear PDFs.
