Full text
XXI Workshop on Neutrino Telescopes The Scattering and Neutrino Detector at the LHC Fabio Alicante Scuola Superiore Meridionale and INFN Napoli On behalf of the SND@LHC Collaboration 01/10/2025
F. Alicante | XXI Workshop on Neutrino Telescopes Potential of high energy neutrino studies at LHC recognised in early 80s • Highest energy man-made neutrino beam • Possibility to study pp→νX in an unexplored range [300 GeV - few TeV] •Large flux in forward region from pp collisions Currently, two experiments in complementary ranges: •SND@LHC off axis: •FASERν on axis: ν 7.2 < η< 8.4 η> 9 Neutrinos at LHC 2 PRL 122.041101
F. Alicante | XXI Workshop on Neutrino Telescopes Neutrino interactions •Measure interactions in the ~TeV energy range. •Large yield of will likely double existing data. QCD •Decays of charm hadrons contribute significantly to the neutrino flux in SND@LHC. •Measure forward charm production with s. •Constrain gluon PDF at very small x. Flavour •Detection of all three types of neutrinos allows for tests of lepton flavour universality. Beyond the Standard Model •Search for new, feebly interacting, particles decaying within the detector or scattering off the target. • magnetic moment and Dark Higgs to . ν ντ νe ντ μ+μ − SND@LHC physics goals 3 Adapted from Juan Rojo's CERN TH seminar DPMJET DPMJET Expected neutrino interactions in RUN3: 250 fb-1
F. Alicante | XXI Workshop on Neutrino Telescopes Veto system • 2 (2022 - 2023) / 3 (2024 - ) scintillator planes • Tag incoming charged particles Target, vertex detector and ECal • ~800 kg tungsten target • Five walls of Emulsion Cloud Chamber (ECC) + five scintillating fibre stations (SciFi) •84 X0, 3λint HCal and muon system • Eight Fe blocks + scintillator planes • Last 3 planes have finer granularity to track muons • (2025) Drift-tube plane •9.5 λint SND@LHC hybrid detector 4 JINST 19 (2024) P05067 Off-axis: 7.2 < η < 8.4 Enhanced flux with charm origin.
F. Alicante | XXI Workshop on Neutrino Telescopes Electronic detectors • 2025 (- ongoing): Recorded 88 fb-1 • 2022 - 2024: Recorded 187 fb-1 •97% detector uptime Emulsion detector •20 emulsion target (~215m2) exposed and developed in 2022-2025 •252 fb-1 integrated • Instrumentation strategy adapted to the optics changes in the years to keep the highest fraction of neutrino interactions Detector operation 5 275 fb-1
F. Alicante | XXI Workshop on Neutrino Telescopes Emulsion scanning is performed with fully automated microscopes in six laboratories: CERN, Bologna, Napoli, Nagoya, Gran Sasso, Santiago Track density up to 4x105 tracks/cm2 Achieved emulsion track position resolution < 150 nm Emulsion scanning and analysis 6 Status of emulsion scanning: 800 Kg x 53 fb-1 Status of emulsion reconstruction: 40 Kg x 70 fb-1 Position resolution σ = 0.13µm SND@LHC Preliminary SND@LHC Preliminary SND@LHC Preliminary Angular resolution σ = 1.1 mrad SND@LHC Preliminary
F. Alicante | XXI Workshop on Neutrino Telescopes •Momentum measurement of charged particles in ECC •Deflection induced by MCS used to infer particle’s momentum •Estimated resolution on simulated charged pions: 15÷25% •Neutrino energy resolution for simulated vertices: ~20% Momentum measurement in emulsion 7 NIM A 574 (2007) 192 Simulation: 40 GeV charged pions Reconstructed vs true muon momentum SND@LHC Simulation SND@LHC Simulation
F. Alicante | XXI Workshop on Neutrino Telescopes Em shower measurements in emulsion 8 Electron neutrino ID based on em shower identification Electron energy estimate based on calorimetric measurements • Reconstruct tracks inside a cylinder • Using vertex tracks as injectors • Based on number of tracks at the shower maximum shower maximum Longitutinal profile Energy calibration Energy resolution SND@LHC Simulation SND@LHC Simulation SND@LHC Simulation
F. Alicante | XXI Workshop on Neutrino Telescopes Passing muons 9 Muon flux is important for detector operations and physics analyses. • Defines the emulsion exposure limit. •Main experimental backgrounds are due to muon interactions. Measurement of flux with 2022 data. • Eur. Phys. J. C (2024) 84: 90 • Excellent agreement between all sub-detectors, including emulsions. • Agreement with MC predictions within 20%. Measurement of the muon flux in heavy ion collisions. • Different physics and LHC optics compared to pp. • Allows for further validation of the background. • Cross-check of detector performance. Muon DIS Muon EM SciFi MC 2025 SND@LHC Preliminary
F. Alicante | XXI Workshop on Neutrino Telescopes 16
F. Alicante | XXI Workshop on Neutrino Telescopes 17
F. Alicante | XXI Workshop on Neutrino Telescopes 18
