Study of the Run-3 muon flux at the SND@LHC experiment

Zamora Saá, J.; Zaffaroni, E.; Yoon, C.S.; Yoo, S.M.; Yazici, C.; Yang, Z.; Yamamoto, S.; Wanke, R.; Vilela, C.; Viegas Guerreiro Leonardo, N.; Verguilov, V.; Vasquez, G.; Vankova-Kirilova, G.; Ursov, E.; Trippl, C.; Tioukov, V.; Timiryasov, I.; Tesarek, J.; Tarek, A.; Steggemann, J.; Starkov, N.; Spurio, M.; Sandoval, O.; Sohn, J.Y.; Soares, G.; Smith, T.E.; Sirri, G.; Siroli, G.P.; Silano, C.; Shibuya, H.; Shchutska, L.; Shchedrina, T.; Shevchenko, V.; Shaposhnikov, M.; Serra, N.; Serban, A.-G.; Sekhniaidze, G.; Schneider, O.; Schmidt-Parzefall, W.; Scalera, V.; Samoilov, M.; Sadykov, Z.; Ruf, T.; Ruchayskiy, O.; Rovelli, T.; Rossolino, N.; Ronchetti, F.; Roganova, T.; Reghunath, A.; Ramos, S.; Quercia, A.; Prota, A.; Primavera, F.; Polukhina, N.; Podgrudkov, D.; Perrotta, A.; Paggi, G.; Ovchynnikov, M.; Okateva, N.; Ogawa, S.; Obayashi, K.; Nuntiyakul, W.; Navarria, F.L.; Mozzina, L.; Morozova, D.; Montesi, M.C.; Mikulenko, A.; Miano, A.; Mei, F.; Majstorovic, M.; Mascellani, A.; Loschiavo, V.P.; Lerner, G.; Lee, W.-C.; Lee, K.S.; Lee, K.Y.; Lauria, A.; Manghi, F.; Lantwin, O.; Landi, I.; Lacker, H.M.; Kuleshov, S.; Konovalova, N.; Komatsu, M.; Klioutchnikov, G.; Kim, Y.G.; Kim, S.H.; Khalikov, E.; Kauniskangas, A.M.; Iuliano, A.; Infantino, A.; Infante Cabanas, S.A.; Ilieva, S.; van Herwijnen, E.; Helo Herrera, J.C.; Hagner, C.; Haefeli, G.J.; Guliaeva, V.; GÜLER, ALİ; Guiducci, L.; Guandalini, C.; Graverini, E.; Golutvin, A.; Giordano, V.; Genovese, K.; Galati, G.; Funk, W.; Fresa, R.; Funicello, N.; Fiorillo, A.; Ferrillo, M.; Fecarotta, O.; Fasanella, D.; Durhan, O.; Donà, R.; Dionisov, I.; Dinc, C.; Di Ferdinando, D.; Di Cristo, C.; Di Crescenzo, A.; Diaz Gutierrez, M.A.; De Rújula, A.; De Pasquale, S.; De Roeck, A.; De Marzi, G.; Del Giudice, G.; de Magistris, M.; De Lellis, G.; de Bryas, P.T.; De Asmundis, R.; Davino, D.; D’Ambrosio, N.; Dallavalle, G.M.; Climescu, M.; Cindolo, F.; Choi, K.-Y.; Chiuchiolo, A.; Chernyavskiy, M.; Chariton, V.; Cervelli, A.; Cerutti, F.; Centanni, D.; Canale, V.; Camporesi, T.; Buontempo, S.; Boyarsky, A.; Bordalo, P.; Bonivento, W.M.; Bonacorsi, D.; Bogomilov, M.; Boccia, V.; Blanco Castro, A.; Biswas, R.; Bick, D.; Betancourt, C.; Bay, A.; Battilana, C.; Bangaru, N.; Ayala Torres, M.A.; Asawatangtrakuldee, C.; Arellano, L.G.; Anokhina, A.; Androsov, K.; Aloschi, F.; Alicante, F.; Alexandrov, A.; Albanese, R.; Ahmad, S.; Abbaneo, D.

doi:10.1140/epjc/s10052-026-15875-x

Study of the Run-3 muon flux at the SND@LHC experiment

Zamora Saá J., Zaffaroni E., Yoon C., Yoo S., Yazici C., Yang Z., ...More

European Physical Journal C, vol.86, no.6, 2026 (SCI-Expanded, Scopus)

Publication Type: Article / Article
Volume: 86 Issue: 6
Publication Date: 2026
Doi Number: 10.1140/epjc/s10052-026-15875-x
Journal Name: European Physical Journal C
Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Aerospace Database, Chemical Abstracts Core, Compendex, INSPEC, zbMATH, Directory of Open Access Journals, Academic Search Ultimate (EBSCO), Engineering Source (EBSCO), Technology Collection (ProQuest)
Open Archive Collection: AVESIS Open Access Collection
Middle East Technical University Affiliated: Yes

Abstract

Long-range muons produced in proton–proton collisions at the ATLAS interaction point constitute the primary background for neutrino interaction searches at the SND@LHC experiment. This work presents a comprehensive characterization of the muon flux throughout LHC Run-3, benchmarking Monte Carlo simulations against experimental measurements. Measured and simulated muon rates agree within 10–15% across all Run-3 configurations. Following the substantial background increase in 2024 as a result of a beam optics change, the reversion to nominal optics in 2025 did not restore the 2022–2023 levels due to the unprecedented adoption of horizontal crossing in ATLAS. As indicated by simulation results, horizontal crossing enhanced the contribution of high-angle muons originating from diffractive proton losses in the LHC Dispersion Suppressor region. Their identification enabled the design of mitigation strategies that were experimentally validated. The simulation framework was also applied to the future high-luminosity LHC configuration, resulting in a considerable muon rate rise, driven by both the planned luminosity increase and the enlarged magnet aperture. Nevertheless, the upgrade from emulsion films to silicon vertex detectors will preserve the efficiency of the experiment even in such a high-rate environment.