nuSTORM: Neutrinos from STORed Muons NuPhys 2014 Queen Mary, University of London Paul Soler, 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 Muon Storage Rings Neutrinos from muon decay in storage rings Decay rings for muons were proposed by Koshkarev (CERN-ISR-DI-74-62) in 1974 and Neuffer (Telemark Conference), 1980 The main motivation is a new type of neutrino beam with well-understood characteristics from decays of muons: This led to developments of modern Neutrino Factories, first proposed by Geer: Phys. Rev D57, 6989 (1998) Simple first step is nuSTORM, decay ring without need for muon cooling or any new technology nuSTORM proposals at Fermilab and CERN: Fermilab LoI (arXiv:1206.0294) and PAC proposal (arXiv:1308.6822) and EoI CERN (arXiv:1305.1419) NuPhys, Queen Mary, Univ. of London: 16 December 2014

nuSTORM: Neutrinos from STORed Muons nuSTORM: storage ring for 3.8 GeV/c muons that can be realised now without any new technology Pions of 5 Gev/c captured and injected into ring. 52% of pions decay to muons before first turn: This creates a first flash of neutrinos from pion decays Ring designed to store muons with p = 3.8 GeV ± 10% Muons decay producing neutrinos: Creates hybrid beam of neutrinos from pion & muon decay 3.8 GeV/c NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 Physics motivation Physics motivation of nuSTORM: Definitive resolution of sterile neutrino problem and search for short-baseline neutrino oscillations Creation of a neutrino beam with a flux accuracy of 10-3 for neutrino scattering physics: “the neutrino light source” Measurement of ne cross sections and nuclear effects in neutrino-nucleus collisions, essential for long baseline neutrino oscillation programme Creation of a test bed for muon accelerator R&D for future high intensity neutrino factories and muon collider A new way of doing neutrino physics NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 Neutrino Factories Neutrino Factories have demonstrated best potential sensitivity for CP violation of all future facilities: However, these are very expensive facilities and very challenging technologically 562 m NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 Long baseline physics Precision requirement for CP violation: For 75% of CP asymmetry coverage at 3s: ACP as low as 5% Requires 1.5% measurement of (~1% syst. error), but we measure rate: Huber, Palmer, Bross arXiv:1411:0629 NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 Long baseline physics Precision requirement for CP violation: In disappearance experiment we can satisfy: In an appearance experiment , so na beam cannot measure Huber, Mezzetto, Schwetz arXiv:0711.2950 CP violation sensitivity for 75% dCP coverage at LBNE Syst. error on ratio in T2HK Difference in and can be large Huber, Palmer, Bross arXiv:1411:0629 NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 Long baseline physics Influence of measurement of cross-sections with less than 1% precision as potentially provided by nuSTORM: Huber, Palmer, Bross arXiv:1411:0629 NuPhys, Queen Mary, Univ. of London: 16 December 2014

Short baseline physics LSND and MiniBooNE hints of and appearance and reactor anomaly (6% deficit) LSND Reactor anomaly MiniBooNE NuPhys, Queen Mary, Univ. of London: 16 December 2014

Short baseline physics Precision requirement for CP violation: nuSTORM could probe all possible sterile neutrino appearance and disappearance channels (if En>t threshold) to test paradigm NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM Parameters nuSTORM flux parameters from end-to-end simulation Pions are captured in horn, transported, and injected into ring. 52% of pions decay to muons before first turn: For 1020 POT, flash of neutrinos from 8.6×1018 pion decays Muon momentum acceptance: (3.8 GeV ± 10%) circulate in ring. Muon lifetime is 27 orbits of decay For 1020 POT, expect 2.6×1017 m+ that decay: Hybrid beam from pion and muon decay for neutrino cross-section measurements and sterile neutrino search 3.8 GeV/c NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM Facility nuSTORM facility: 120 GeV protons on carbon or inconel target (100 kW) NuMI-style horn for pion collection: recently optimised Injection pions (5 GeV/c ± 10%) into storage ring: 0.09 p/POT Storage ring: large aperture FODO lattice (3.8 GeV/c ± 10%) muons: 8×10-3 m/POT NuPhys, Queen Mary, Univ. of London: 16 December 2014

nuSTORM Flux and Spectrum nuSTORM flux and energy spectrum nm from pion decay flux: 6.3×1016 n/m2 at 50 m ne from muon decay flux: 3.0×1014 n/m2 at 50 m nm from kaon decay flux: 3.8×1014 n/m2 at 50 m Can be used for cross-section measurements and short baseline experiments Use muon decay neutrinos to calibrate hadron decay neutrinos? NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM Event Rates Flux uncertainties for nuSTORM from beam diagnostics: < 1% Event rates per 1021 POT in 100 ton Liquid Argon at 50 m Limited by detector systematics: NuPhys, Queen Mary, Univ. of London: 16 December 2014

Neutrino interactions at nuSTORM Very rich physics programme (just some examples): Electron neutrino and cross-section measurements p0 production in neutrino interactions Charged p and K production Neutrino-electron scattering Neutrino-nucleon scattering: charged current and neutral current (NC/CC ratio and sin2qW) Nuclear effects in neutrino interactions Semi-exclusive and exclusive processes: measurement of production New physics and exclusive processes: test of universality, heavy neutrinos, eV-scale pseudo-scalar penetrating particles …. Over 60 physics topics already identified: PhD theses NuPhys, Queen Mary, Univ. of London: 16 December 2014

Neutrino interactions at nuSTORM Example of CCQE measurement: Data for and cross-sections NuPhys, Queen Mary, Univ. of London: 16 December 2014

Possible near detectors at nuSTORM Example of near detectors: HiResMuNu like in LBNF High pressure Ar gas LBNO near detector WA105: 300 ton LAr Demonstrator? NuPhys, Queen Mary, Univ. of London: 16 December 2014

First attempt at generic reconstruction Geant4 generic simulation for near detector: Totally Active Scintillator with Magnetised Iron Detector Reconstruction of Particle identification: R. Bayes Very preliminary NuPhys, Queen Mary, Univ. of London: 16 December 2014

Sterile neutrino search Assume two detectors: Super-saturated Magnetised Iron: SuperBIND Magnetic field: 1.5-2.6 T 240 kA from 8 Superconducting Trasmission Lines NuPhys, Queen Mary, Univ. of London: 16 December 2014

Sterile neutrino search Appearance search: Disappearance search: Adey et al., PRD 89 (2014) 071301 With full reconstruction and efficiencies, 1021 POT NuPhys, Queen Mary, Univ. of London: 16 December 2014

Sterile neutrino search Short-baseline oscillation search with near detector at 50 m and far detector at 2 km, 1021 POT exposure Appearance and disappearance multi-variate analyses Adey et al., PRD 89 (2014) 071301 Appearance efficiencies Disappearance efficiencies NuPhys, Queen Mary, Univ. of London: 16 December 2014

Sterile neutrino search Short-baseline oscillation search with near detector at 50 m and far detector at 2 km, 1021 POT exposure Appearance and disappearance multi-variate analyses Adey et al., PRD 89 (2014) 071301 Appearance sensitivity Disappearance sensitivity 99% Still need to show combined analysis appearance/disappearance NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 Muon Accelerator R&D Path towards Neutrino Factory and Muon Collider NuPhys, Queen Mary, Univ. of London: 16 December 2014

nuSTORM for Muon Accelerator R&D nuSTORM: testbed for 6D muon cooling experiment At end of straight: 3.5 m iron pion absorber After absorber: 1010 m/pulse between 100-300 MeV/c NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM at Fermilab nuSTORM could be sited at Fermilab Total cost: $330 M Near Detector Hall Far Detector Hall (D0) Target building Decay ring NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM at CERN? However, P5 report was not supportive at Fermilab (probably due to high cost and interference with LBNF) Explore siting at CERN? Make the most of Neutrino Platform at new facility in North Area M. Nessi NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM at CERN? Target station in North Area For two detector oscillation search: near detector in North Area and far detector in Point 1.8 NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM at CERN? nSTORM serving the Neutrino Platform at CERN M. Nessi et al. NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM at CERN? nSTORM serving the Neutrino Platform at CERN M. Nessi et al. NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 nuSTORM at CERN? nSTORM serving the Neutrino Platform at CERN M. Nessi et al. NuPhys, Queen Mary, Univ. of London: 16 December 2014

NuPhys, Queen Mary, Univ. of London: 16 December 2014 Conclusions nuSTORM is entry level Neutrino Factory that can be built now, without need of new technology like cooling It complements long baseline programme: it measures all cross-sections with high precision due to <1% knowledge of flux, and resolves systematic errors for long-baseline It would be the ultimate neutrino scattering facility: “a neutrino light source”, or the “LEP for neutrinos” Serves as test-bed for muon acceleration R&D for future of particle physics (energy and intensity frontier) A scenario of LBNF in USA, Hyper-KamiokaNDE in Japan and nuSTORM at CERN would make a truly worldwide programme The question shouldn’t be: “Can we afford nuSTORM?” but instead: “Can we afford not to have nuSTORM?” NuPhys, Queen Mary, Univ. of London: 16 December 2014