标题： 首次在LHC使用FASER测量μ中微子相互作用截面和流随能量的变化 显示英文标题

标题： First Measurement of the Muon Neutrino Interaction Cross Section and Flux as a Function of Energy at the LHC with FASER

摘要： 这封信件展示了在钨中能量依赖性的中微子-核子截面的测量以及μ中微子和反中微子的微分流。分析使用了质心能量为$13.6 \, {\rm TeV}$和对应积分为$(65.6 \pm 1.4) \, \mathrm{fb^{-1}}$的质子-质子碰撞数据。利用 FASER 探测器的有源电子组件，识别出$338.1 \pm 21.0$个带电电流μ中微子相互作用事件，并减去了来自其他过程的背景。我们将中微子事件展开到与 FASER 探测器敏感区域相对应的有效体积内，并以两种方式解释结果：我们使用预期的中微子通量来测量截面，以及使用预测的截面来测量中微子通量。两个结果都以六个中微子能量区间呈现，实现了TeV范围内的首次微分测量。观察到的分布与标准模型预测一致。利用这些微分数据，我们提取了来自π介子和K介子衰变的中微子贡献。 显示英文摘要

摘要： This letter presents the measurement of the energy-dependent neutrino-nucleon cross section in tungsten and the differential flux of muon neutrinos and anti-neutrinos. The analysis is performed using proton-proton collision data at a center-of-mass energy of $13.6 \, {\rm TeV}$ and corresponding to an integrated luminosity of $(65.6 \pm 1.4) \, \mathrm{fb^{-1}}$. Using the active electronic components of the FASER detector, $338.1 \pm 21.0$ charged current muon neutrino interaction events are identified, with backgrounds from other processes subtracted. We unfold the neutrino events into a fiducial volume corresponding to the sensitive regions of the FASER detector and interpret the results in two ways: We use the expected neutrino flux to measure the cross section, and we use the predicted cross section to measure the neutrino flux. Both results are presented in six bins of neutrino energy, achieving the first differential measurement in the TeV range. The observed distributions align with Standard Model predictions. Using this differential data, we extract the contributions of neutrinos from pion and kaon decays.