论文标题
LHC的正向物理设施和质子中的内在魅力的魅力梅森和中微子的巨大生产
Far-forward production of charm mesons and neutrinos at Forward Physics Facilities at the LHC and the intrinsic charm in the proton
论文作者
论文摘要
我们讨论了远方的$ d $ erson/antimess和中微子/抗神经药的生产，它们在LHC的pp collisions中的半衰减衰减中的生产。我们将Gluon-Gluon Fusion $ gg \ \ to c \ bar {c} $，固有的魅力（IC）$ gc \ to gc $以及重组$ gq \ to dc $ partsonic机制。计算是在$ k_t $ -FACTORIZARIZIAD方法和混合模型中使用不同的未集成的Parton分布功能（UPDF）以及文献中的gluons以及Collinear方法中的。我们将结果与forward $ d^{0} $ - 梅森生产的LHCB数据进行比较，以$ \ sqrt {s} = 13 $ tev的不同速度箱，以$ 2 <y <4.5 $。在LHCB运动学上，IC和重组模型可以忽略不计。两种机制在较大的速度上都开始至关重要，并且在标准魅力生产机制上占主导地位。到目前为止，还没有探测该区域的实验。我们还提供了前向电子，MUON和TAU中微子的能量分布，该中微子将通过当前运行的Faser $ν$实验在LHC上测量，以及Faser $ \ nu2 $或Flare等未来实验，该实验最近由远期物理学设施项目提出。再次显示不同机制的组成部分。对于各种中微子（电子，Muon，tau），均匀的贡献，即IC和/或重组，重新组合，主导于Light Meson（Pion，Kaon）以及由Gluons融合的Neutrino Entrino Energies $e_ce_ν\ gtrsim 300 $ GEV造成的标准魅力产生贡献。对于电子和MUON中微子而言，这两种机制都会导致相似的生产率，并且它们的分离似乎是不可能的。另一方面，对于$ν_τ + {\barν}_τ$中微子通量，重组将进一步减少，从而使IC贡献的测量非常有吸引力。
We discuss production of far-forward $D$ mesons/antimesons and neutrinos/antineutrinos from their semileptonic decays in pp-collisions at the LHC. We include the gluon-gluon fusion $gg \to c\bar{c}$, the intrinsic charm (IC) $gc \to gc$ as well as the recombination $gq \to Dc$ partonic mechanisms. The calculations are performed within the $k_T$-factorization approach and the hybrid model using different unintegrated parton distribution functions (uPDFs) for gluons from the literature, as well as within the collinear approach. We compare our results to the LHCb data for forward $D^{0}$-meson production at $\sqrt{s} = 13$ TeV for different rapidity bins in the interval $2 < y < 4.5$. The IC and recombination models are negligible at the LHCb kinematics. Both the mechanisms start to be crucial at larger rapidities and dominate over the standard charm production mechanisms. At high energies there are so far no experiments probing this region. We present also energy distributions for forward electron, muon and tau neutrinos to be measured at the LHC by the currently operating FASER$ν$ experiment, as well as by future experiments like FASER$\nu2$ or FLArE, proposed very recently by the Forward Physics Facility project. Again components of different mechanisms are shown separately. For all kinds of neutrinos (electron, muon, tau) the subleading contributions, i.e. the IC and/or the recombination, dominate over light meson (pion, kaon) and the standard charm production contribution driven by fusion of gluons for neutrino energies $E_ν \gtrsim 300$ GeV. For electron and muon neutrinos both the mechanisms lead to a similar production rates and their separation seems rather impossible. On the other hand, for $ν_τ + {\bar ν}_τ$ neutrino flux the recombination is further reduced making the measurement of the IC contribution very attractive.
