1. Detector R&D for Future Neutrino Oscillation Facilities (Solid Detectors) NUFACT08 Valencia, Spain 30 June 2008 Paul Soler

2. 2 NUFACT08 Valencia, 30 June 2008 Outline 1.Motivation: neutrino mixing, oscillations, degeneracies and unknown parameters 2.International Scoping Study 3.Magnetised Iron Neutrino Detector (MIND) 4.Totally Active Scintillator Detector (TASD) 5.Near detector 6.R&D plans in Europe 7.Neutrino Factory roadmap

3. 3 NUFACT08 Valencia, 30 June 2008 Neutrino mixing o Weak eigenstates do not have to coincide with mass eigenstates Ignoring Majorana phases  1 and  2, the neutrino mixing matrix (Pontecorvo- Maki-Nakagawa-Sakata, PMNS matrix) is similar to CKM matrix for quarks. whereandStates:

4. 4 NUFACT08 Valencia, 30 June 2008 Neutrino oscillations Minakata & Nunokawa JHEP 2001 o Matter oscillation results for three neutrinos: where is for (MSW effect)

5. 5 NUFACT08 Valencia, 30 June 2008 Neutrino oscillations Magic baseline: Only one term in equation Clean determination of  13 o Matter oscillation results for three neutrinos: where is for (MSW effect) However, there are up to 8 degeneracies and correlations between variables that need to be determined. Strategy: different experiments at different baselines and energies to solve degeneracies

6. 6 NUFACT08 Valencia, 30 June 2008 Unknown parameters o Consistent picture emerging o Global fit provides:  sin 2  12 =0.32  0.23   m 12 2 =7.6  0.20×10 -5 eV 2  sin 2  23 =0.50  0.063   m 23 2 =2.4  0.15×10 -3 eV 2 Schwetz o Unknown quantities:  sin  13 <0.224 (@3  ),  Mass hierarchy: sign  m 13 2  CP violation phase  InvertedNormal

7. 7 NUFACT08 Valencia, 30 June 2008 International Scoping Study o The International Scoping Study looked at the physics, accelerator and detector prospects for future neutrino oscillation facilities to determine remaining unknown oscillation parameters o Outcomes have been published as three reports: arXiv: 0712.4129 arXiv: 0802.4023v1 arXiv: 0712.4129

8. 8 NUFACT08 Valencia, 30 June 2008 International Scoping Study o The International Scoping Study (ISS) compared the physics performance and detector requirements for three possible facilities: ̶ Super-beams: high powered conventional neutrino beams from the decay of pions ̶ Neutrino Factories: neutrino beams from the decay of muons ̶ Beta beams: neutrino beams from the decay of radioactive isotopes o Additionally, the ISS defined the scope of the accelerator parameters for a: ̶ Neutrino Factory ̶ Beta beam facility (in collaboration with the Eurisol beta beam design study)

9. 9 NUFACT08 Valencia, 30 June 2008 Superbeams o Super-beams: 1-4 MW proton intensity to generate beam of neutrinos from the decays of pion and kaons. Decay Pipe  Target Horns Detector  Off-axis for better determination neutrino energy. No a off-axis (~750 km) or T2K (~250 km)  ’s:   →    K + →    e ’s:   →e  e  K + →   e  e Off-axis: narrower energy band M. Zito to report at this meeting

10. 10 NUFACT08 Valencia, 30 June 2008 Neutrino Factory o Neutrino Factories produce neutrinos from muon decays in a storage ring. o Rate calculable by kinematics of decay (Michel spectrum)  For example, if  + accelerated to 25 GeV: o Defines detector requirements: ̶ Since muon and electron neutrino and anti-neutrino species are produced simultaneously we need to determine the charge and lepton identity to separate from background  Magnetic detectors. 0 5 10 15 20 25 Neutrino Energy (GeV)

11. 11 NUFACT08 Valencia, 30 June 2008 Neutrino Factory o Baseline design for a Neutrino Factory from International Design Study o Design can fire neutrino beams to two different detectors at two different baselines o Neutrino factory can provide sufficient neutrino luminosity to perform CP violation experiments at very long baselines 3000-7500 km.

12. 12 NUFACT08 Valencia, 30 June 2008 Beta Beams o Beta beam: beta decay of accelerated radioactive nuclei (P. Zucchelli, Phys. Lett. B, 532 (2002), 166-172.) – He-6 for neutrino production:  ~ 100 – Ne-18 for antineutrino production:  ~ 60 Only one neutrino species  do not need magnetic detector! Eurisol study E. Wildner to report at this meeting

13. 13 NUFACT08 Valencia, 30 June 2008 International Scoping Study (Detectors) o Detector requirements established by International Scoping Study for a Neutrino Factory Detector Report (arxiv:0712.4129v1 [physics.ins-det]) o Baseline detector requirements are: ̶ Two detectors at 4000 km and 7500 km to solve degeneracies  For a Neutrino Factory facility: ̶ Magnetised Iron Neutrino Detector (MIND) of 50 kton fiducial for  appearance channel (gold channel) ̶ Possible addition of Magnetised EmulsionCloud Chamber (MECC) of 10 kton for  appearance (silver channel)  Beyond the baseline improvements for Neutrino Factory include e appearance (platinum) channels (R&D needed): ̶ Magnetised Liquid Argon: 10-100 kton ̶ Magnetised Totally Active Scintillating Detector (TASD): 20-30 kton o For a Superbeam or Beta-beam facility: do not need magnetisation ̶ Baseline is Water Cherenkov detector (~500 kton) ̶ Other options: Liquid Argon or Totally Active Scintillating Detector (ie. No a)

14. 14 NUFACT08 Valencia, 30 June 2008 Magnetised Iron Neutrino Detector (MIND) o Golden channel signature: “wrong-sign” muons in magnetised calorimeter o Far detector (3000-7000 km) can search for “wrong-sign” muons in appearance mode (for example, Large Magnetic Detector) Magnetic Iron Neutrino Detector (MIND) iron (4 cm) + scintillators (1cm) beam 20 m B=1 T 50KT 50% wrongsignmuondetector (Cervera et al. 2000)

15. 15 NUFACT08 Valencia, 30 June 2008 MIND analysis Including QE EE E had E  “Golden” paper (Cervera et al, 2000) was optimised for a small value of  13, so efficiency at low energy cut severely oUsed fast simulations and detector parameterisation oMIND analysis redone for ISS (Cervera 2007) ̶ Improved event selection, ̶ Fast simulation ̶ Perfect pattern recognition ̶ Reconstruction based on parameterisation ̶ Dipole field instead of toroidal field ̶ Fully contained muons by range ̶ Scraping muons by curvature ̶ Hadron shower:

16. 16 NUFACT08 Valencia, 30 June 2008 E E MIND analysis o Kinematic analysis to eliminate background o Variables used:  Q t =P  sin 2  P  =|P  |  Cuts in E -P  and E -Q t planes o Main background: hadron decay (charm decay in CC and pion decay in NC) not detected CC Hadron decay NC Pion decay

17. 17 NUFACT08 Valencia, 30 June 2008 MIND event selection oMuons go beyond the hadron shower oThey can be identified by range oClassification of Charged Current events depends on muon ID oMuon identification criteria attempted: ̶ L  -L had > 75 cm ̶ L  -L had > 150 cm ̶ L  -L had > 200 cm

18. 18 NUFACT08 Valencia, 30 June 2008 MIND background oBackgrounds from charm, NC and charge misidentification Charge mis-ID

19. 19 NUFACT08 Valencia, 30 June 2008 MIND Efficiency oSignal efficiency: ̶ Efficiency plateau between 5 and 8 GeV ̶ Baseline: L  > 150 cm ̶ Ensures charge mis-ID below 10 -3 Old analysis II: P  >5 GeV, Q t > 0.7 GeV Old analysis I: P  >7.5 GeV, Q t > 1 GeV  CC signal L  > 75 cm L  >150 cm L  >200 cm oImprovements to study: MIND analysis with full GEANT4 reconstruction International Scoping Study (ISS) report A. Laing to report at this meeting on new developments on this analysis

20. 20 NUFACT08 Valencia, 30 June 2008 MIND sensitivity  Performance of IDS-NF baseline detectors (two MIND detectors, one at 4000 km and one at 7500 km) at 3  (Huber, Winter, ISS 2007) o Efficiencies and background used are those from latest MIND analysis

21. 21 NUFACT08 Valencia, 30 June 2008 Magnetised Iron Neutrino Detector R&D o R&D: development of scintillator bars and readout system through fibres, electronics … Extruded scintillator: pioneered Fermilab o Photon detectors: APD, MPPC … o Build prototype for test beam o Engineering: Magnetic field Multi-Pixel-Photon-Counter ~20 m

22. 22 NUFACT08 Valencia, 30 June 2008 o Indian Neutrino Observatory (INO) in advanced stage of planning o Recommended for funding o Detector size: 48 m x 16 m x 16 m o Readout: RPCs o B=1.5 T  Physics case: atmospheric oscillations with magnetised detector, matter effects, sign  m 2 23,  23, CP, CPT, ultrahigh energy and  o Far detector at magic baseline of neutrino factory for most facilities: ̶ CERN to INO: distance = 7152 km ̶ JPARC to INO: distance = 6556 km ̶ RAL to INO: distance = 7653 km Indian Neutrino Observatory INO at ideal position! A. Raychaudhuri to report at this meeting

23. 23 NUFACT08 Valencia, 30 June 2008 MIND: new developments oImprovements MIND analysis with full GEANT4 reconstruction Demonstrate that for E < 10 GeV Backgrounds are below 10 -3 The efficiency can be increased with respect to fast analysis Compute: Signal and backgrounds efficiency as a function of energy Energy resolution as a function of energy Optimise segmentation and B field based on the above parameters and taking into account feasibility and cost Add Quasi-Elastic (QE) and Resonance (RES) production to Deep Inelastic (DIS) events

24. 24 NUFACT08 Valencia, 30 June 2008 MIND software framework

25. 25 NUFACT08 Valencia, 30 June 2008 Kalman filter (RecPack) oAlready started implementing pattern recognition and Kalman filter (A. Laing) ̶ Kalman filter algorithm takes into account multiple scattering and energy loss  2 /DOF ~ 1 shows model working well

26. 26 NUFACT08 Valencia, 30 June 2008 Kink rejection oFurther rejection background due to charge mis-id: ̶ 70-80% events due to hard scatters (kinks) ̶ Rest due to Non-Gaussian MS ̶ Established kink finding algorithm (cut on maximum  2 hit of track) A. Laing

27. 27 NUFACT08 Valencia, 30 June 2008 Totally Active Scintillating Detectors (TASD) Possible improvement: Totally Active Scintillating Detector (TASD) using No a and Miner a concepts 3 cm 1.5 cm 15 m 100 m –3333 Modules (X and Y plane) –Each plane contains 1000 slabs –Total: 6.7M channels o Momenta between 100 MeV/c to 15 GeV/c o Magnetic field considered: 0.5 T o Reconstructed position resolution ~ 4.5 mm Ellis, Bross Reduction threshold: access second oscillation maximum and electron identification

28. 28 NUFACT08 Valencia, 30 June 2008 Totally Active Scintillating Detectors (TASD) Neutrino CC reconstructed efficiency Muon charge mis-ID rate A. Bross to report on new developments at this meeting Other unknown: what is electron identification efficiency?

29. 29 NUFACT08 Valencia, 30 June 2008 Totally Active Scintillating Detectors (TASD) However, possible magnetisation can be achieved using magnetic cavern concept (10 modules with 15m x 15 m diameter) Bross Use Superconducting Transmission Line (STL): cable has its own cryostat! 0.58 T at 50 kA Developed for VLHC R&D needed to develop concept!! Main problem: magnetisation of huge volume (difficulty and cost)

30. 30 NUFACT08 Valencia, 30 June 2008 o Possible use of TASD opens up possibility of running at a low energy neutrino factory (4 GeV) Totally Active Scintillating Detectors (TASD) Bross, Ellis, Geer, Mena, Pascoli 95% CL mass hierarchy at 1480 km 95% CL CP violation at 1480 km

31. 31 NUFACT08 Valencia, 30 June 2008 Hybrid detectors MIND+TASD? MIND TASD muon ~1-2m hadron shower MIND electron shower o Compromise between MIND and TASD concepts? Optimisation of geometry not done o Iron free regions: improve momentum and charge determination o Combining MIND+TASD and iron-free regions ? Iron (2cm) + active (4cm) air + active (1cm) hadron shower muon Scintillator iron

32. 32 NUFACT08 Valencia, 30 June 2008 Hybrid Emulsion Detectors Plastic base Pb Emulsion layers  1 mm  Emulsion detector for  appearance, a la OPERA: “silver channel” Emulsion Cloud Chamber (ECC)  Issues: high rate, selected by choosing only “wrong sign”  →  events o Assume a factor of two bigger than OPERA (~4 kt) A. Cazes to report OPERA status at this meeting

33. 33 NUFACT08 Valencia, 30 June 2008 Magnetised Emulsion Cloud Chamber Electronic det: e/  separator & “Time stamp” Rohacell® plate emulsion film stainless steel plate spectrometertargetshower absorber Muon momentum resolution Muon charge misidentification Scotto Lavina to update status at this meeting

34. 34 NUFACT08 Valencia, 30 June 2008 Hybrid Emulsion Detectors o For 60 walls emulsion  1.1M bricks  4.1 kton o Total length of detector is: ~ 150 m Possible design hybrid emulsion-scintillator far detector Golden and silver channels simultaneously! supermodule 8 m Target Trackers Pb/Em. target ECC emulsion analysis: Vertex, decay kink e/  ID, multiple scattering, kinematics Extract selected brick Pb/Em. brick 8 cm Pb 1 mm Basic “cell” Emulsion Electronic detectors: Brick finding, muon ID, charge and p Link to muon ID, Candidate event Spectrometer  p/p<20%

35. 35 PPE Review 2-3 June 2008 Muon chambers EM calorimeter Hadronic Calorimeter o Near detectors should be able to measure flux and energy of and o High event rate: ~10 9 CC events/year in 50 kg detector o Calibration and flux control (inverse muon decay): Near detector o Near Detector flux control for oscillation measurements o Measure neutrino cross-sections and charm cross-section in Near Detector to control systematics of far detector (main background) 10 5 -10 6 events/yr See poster A.Laing, PS

36. 36 PPE Review 2-3 June 2008 Charm measurement for NF o Motivation: measure charm cross-section to validate size of charm background in wrong-sign muon signature o Charm cross-section and branching fractions poorly known o Semiconductor vertex detector only viable option in high intensity environment to measure charm: Charm ̶ Studies of Monolithic Active Pixel Sensors (MAPS) for NuFact near detector, work with Vanilla, HEPAPS Status charm cross-sections: F. Di Capua

37. 37 NUFACT08 Valencia, 30 June 2008 European Effort o EuroNu: four year EU Design Study for “A High Intensity Neutrino Oscillation Facility in Europe” (Super-beam, Neutrino Factory, Beta-beam, neutrino detectors and physics performance). ̶ Neutrino detectors: study Magnetised Neutrino Iron Detector (MIND) performance for golden measurement at a neutrino factory, water Cherenkov detector for beta and super beams and near detectors for all facilities o DevDet is an Integrating Activity proposal across Europe to coordinate “Detector Development Infrastructures for Particle Physics Experiments” ̶ It includes detector R&D for future accelerator-driven neutrino facilities ̶ The aim is to develop test beams for neutrino detector R&D

38. 38 NUFACT08 Valencia, 30 June 2008 Test Beam Facility for Neutrino Detector R&D oRequest test beam in East Area at the CERN PS, with a fixed dipole magnet for dedicated Neutrino Detector R&D Liquid Argon tests, beam telescopes for silicon pixel and SciFi tests, calorimetry … Neutrino detector test facility: resource for all European neutrino detector R&D

39. 39 NUFACT08 Valencia, 30 June 2008 MIND prototypes for Test Beam oPrototype MIND (“BabyMind”): A. Cervera How big do we make test beam detector? Current default is ~2x2x4 m 3 ie. ~10 -3 of full MIND Important to contain  < 2 GeV oCollaboration with INO: set up test stand in a beam environment: ̶ Nearly the same as “BabyMind” ̶ Main difference: dipole vs toroidal field ̶ Orientation of iron plates Probably not an issue

40. 40 NUFACT08 Valencia, 30 June 2008 Neutrino Oscllation Measurement Roadmap oRoadmap for Neutrino Oscillation measurements: ̶ The ISS studied options for future facilities and narrowed the list of detector options for each facility ̶ Launch of Neutrino Factory International Design Study (IDS) ̶ Developed an internationally agreed baseline for the Neutrino Factory accelerator complex and for the Neutrino Factory neutrino- detection system ̶ Goal: to produce a ‘Reference Design Report’ for the Neutrino Factory by 2012:  The RDR is conceived as the document that will allow the to consider initiating the Neutrino Factory project  Emphasis on engineering to demonstrate technical feasibility and evaluate cost

41. 41 NUFACT08 Valencia, 30 June 2008 Neutrino Oscillation Measurement Roadmap oRoadmap for Neutrino Oscillation measurements: ̶ Knowledge of  13 and technical feasibility dictates high intensity neutrino facility for high-precision required ‘second half next decade’

42. 42 NUFACT08 Valencia, 30 June 2008 Neutrino Factory Roadmap?