Latest neutrino results from the FASER experiment and their implications for forward hadron production

作者：FASER Collaboration, Roshan Mammen Abraham, X. Ai, S. Alonso Monsalve, J. K. Anders, C. Antel, A. Ariga, T. Ariga, Jeremy Atkinson, F. U. Bernlochner, Tobias Boeckh, J. Boyd, Lydia Brenner, A. M. Burger, F. Cadoux, R. Cardella, D. Casper, Charlotte Cavanagh, X. Chen, Dhruv Chouhan, A. Coccaro, Stephane Débieux, Ansh Desai, Sergey Dmitrievsky, Radu Dobre, Monica D'Onofrio, Sinead Eley, Yannick Favre, Jonathan L. Feng, Carlo Alberto Fenoglio, D. Ferrère, Max Fieg, Wissal Filali, Elena Firu, Haruhi Fujimori, Edward Karl Galantay, Ali Garabaglu, S. M. Gibson, S. González-Sevilla, Y. Gornushkin, Yotam Granov, C. B. Gwilliam, D. Hayakawa, M. Holzbock, S.‐C. Hsu, Z. Hu, G. Iacobucci, Tomohiro Inada, Luca Iodice, S. Jakobsen, Hans Ludwig Joos, E. Kajomovitz, H. Kawahara, Alex Keyken, Felix Kling, Daniela Köck, P. Kontaxakis, U. Köse, Rafaella Kotitsa, Peter Krack, S. Kuehn, T. Kugathasan, Sebastian Laudage, L. J. Levinson, Botao Li, Jinfeng Liu, Yi Liu, Margaret Lutz, J. C. MacDonald, Chiara Magliocca, Toni Mäkelä, Lawson McCoy, J. A. Mcfayden, Andrea Pizarro Medina, Matteo Milanesio, Théo Moretti, K. Moriyama, Mitsuhiro Nakamura, Toshiyuki Nakano, Laurie Nevay, K. Ohashi, H. Otono, Lorenzo Paolozzi, Pawan Pawan, Brian Petersen, Titi Preda, M. T. Prim, M. Queitsch-Maitland, Juan Rojo, Hiroki Rokujo, André Rubbia, J. A. Sabater Iglesias, Osamu Sato, P. Scampoli, K. Schmieden, M. Schott, C. Sebastiani, A. Sfyrla, D. Sgalaberna, M. Shamim, Savannah Shively, Yosuke Takubo, Noshin Tarannum, O. Theiner, Simon Thor, E. Torrence, Oscar Ivan Valdes Martinez, S. Vasina, B. Vormwald, Yuxiao Wang, Eli Welch, M. Wielers, Benjamin James Wilson, Jialin Wu, Johannes Wüthrich, Y. Xu, Daichi Yoshikawa, Stefano Zambito, Shunliang Zhang, Zhao, Xingyu · 发表于：arXiv (Cornell University) · 年份：2025 · DOI：10.48550/arxiv.2507.23552 · 被引用次数：2 · 研究领域：Particle physics theoretical and experimental studies、Particle accelerators and beam dynamics、Superconducting Materials and Applications

The muon puzzle -- an excess of muons relative to simulation predictions in ultra-high-energy cosmic-ray air showers -- has been reported by many experiments. This suggests that forward particle production in hadronic interactions is not fully understood. Some of the scenarios proposed to resolve this predict reduced production of forward neutral pions and enhanced production of forward kaons (or other particles). The FASER experiment at the LHC is located 480 m downstream of the ATLAS interaction point and is sensitive to neutrinos and muons, which are the decay products of forward charged pions and kaons. In this study, the latest measurements of electron and muon neutrino fluxes are presented using the data corresponding to 9.5 $\mathrm{fb^{-1}}$ and 65.6 $\mathrm{fb^{-1}}$ of proton-proton collisions with $\sqrt{s}=13.6~\mathrm{TeV}$ by the FASER$ν$ and the FASER electronic detector, respectively. These fluxes are compared with predictions from recent hadronic interaction models, including EPOS-LHCr, SIBYLL 2.3e, and QGSJET 3. The predictions are generally consistent with the measured fluxes from FASER, although some discrepancies appear in certain energy bins. More precise flux measurements with additional data will follow soon, enabling validation of pion, kaon, and charm meson production with finer energy binning, reduced uncertainties, and multi-differential analyses.