Detector Working Group: review of progress, issues to be addressed 4th Neutrino Factory International Design Study Meeting, Mumbai Joint with EUROnu Meeting 12 October 2009 Paul Soler

4th Neutrino Factory International Design Study Meeting Contents Detector requirements Magnetised Iron Neutrino Detector (MIND) Indian Neutrino Observatory Totally Active Scintillator Detectors (TASD) Water Cherenkov Liquid Argon Emulsion Cloud Chamber (ECC) Near Detector Detector R&D 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Detector requirements Detector requirements established by International Scoping Study (ISS) for a Neutrino Factory Detector Report: (arxiv:0712.4129v1 [physics.ins-det], JINST 4:T05001,2009) Baseline detector requirements are: Two detectors at 4000 km and 7500 km Magnetised Iron Neutrino Detector (MIND) of 50 kton fiducial (gold channel) Possible addition of Magnetised Emulsion Cloud Chamber (MECC) of 10 kton (silver) Beyond the baseline improvements for platinum channels (R&D needed): Magnetised Liquid Argon: 10-100 kton Magnetised Totally Active Scintillating Detector (TASD): 20-30 kton Near detectors: magnetised to measure flux and hadron background 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Magnetised Iron Neutrino Detector (MIND) M~50-100 Kton 50-100 m 15-20 m 1cm transverse resolution n beam From ISS report: 15-20 m Old analysis II: Pμ>5 GeV, Qt> 0.7 GeV Old analysis I: Pμ>7.5 GeV, Qt> 1 GeV nmCC signal Lμ> 75 cm Lμ>150 cm Lμ>200 cm B=1 T Advantages: Easy to detect sign of muons Easy to discriminate hadronic showers Easy to magnetise Based on known technology Can be very massive 50-100 kton Cost is not prohibitive: $300M-$400M Disadvantages: Difficult (not impossible!) to detect electrons Cannot detect taus Energy threshold too high for 2nd maximum iron (4 cm) scintillators (1 cm) 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Magnetised Iron Neutrino Detector (MIND) Performance of IDS-NF baseline detectors (two MIND detectors, one at 4000 km and one at 7500 km) at 3s, from ISS Physics report (arXiv:0710.4947 [hep-ph], Rept.Prog.Phys.72:106201,2009.) 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Simulation and resolution (from ISS) GEANT3 simulation Detector effects not simulated Perfect pattern recognition Reconstruction based on parameterisation Dipole field instead of toroidal Fully contained muons by range Scaping muons by curvature Hadron shower: Ehad Em Including QE 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting MIND analysis Kinematic analysis to eliminate background Variables used: En Pm=|Pm| Qt=Pmsin2 q q Cuts in En-Pm and En-Qt planes Main background: hadron decay (charm decay in CC and pion decay in NC) not detected CC Hadron decay NC Pion decay 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting MIND background Backgrounds from charm, NC and charge misidentification Charge mis-ID 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Aims of full simulation/reconstruction Need to verify results with full simulation/reconstruction Demonstrate that for En < 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 Identify crucial parameters to be optimised to maximise the sensitivity to the osc. parameters Optimise segmentation and B field based on the above parameters and taking into account feasibility and cost 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Detector optimisation: Longitudinal segmentation Move from 4 cm Fe + 1 cm scintillator to 3 cm Fe + 2 cm scintillator 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Detector optimisation: Transverse segmentation Assuming perfect pattern recognition 1 cm transverse resolution is enough for charge and Qt measurements Pattern recognition: better segmentation should improve it which resolution saturates the patter recognition performance ? 1 cm transverse segmentation looks appropriate Lines: 1, 1.5 and 2 GeV/c muon momentum BFe=1.25 Tesla Fe thickness = 4 cm BFe=1.25 Tesla Fe thickness = 2.5 cm BFe=2 Tesla Fe thickness = 2.5 cm 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Detector optimisation: magnetic field Even if we are able to isolate a 1 GeV/c muon, the ratio curvature/MS is not sufficient. ~5% charge mis-ID The magnetic field strength is the crucial parameter Going from 1.25 to 1.7 Tesla average is feasible (J. Nelson, Golden07) > 1 o.o.m improvement at 1 GeV/c. 10-3 level MINOS MIND 1 GeV/c 2 GeV/c 1.5 GeV/c 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Prospects MIND Analysis work Fast simulation/reconstruction was very useful For more than a year we have been developing a full simulation to address: What are the main backgrounds at low energies ? What is the background level ? Where is the efficiency plateau ? What are the parameters to be optimised ? Prototyping R&D program should go in parallel to validate assumptions 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

MIND software framework ✔ 1/2 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Kalman filter (RecPack) Pattern recognition and Kalman filter already implemented Kalman filter algorithm takes into account multiple scattering and energy loss c2/DOF ~ 1 shows model working well 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting Kink rejection Further rejection background due to charge mis-id: Established kink finding algorithm (cut on maximum c2 hit of track) to get rid of non-Gaussian scatters ~70% bck A. Laing to report at this meeting improve- ments pattern recognition, analysis and comparison to previous simulations 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Indian Neutrino Observatory Indian Neutrino Observatory (INO): Main purpose: atmospheric neutrinos Can be used for beam neutrinos Detector size: 48 m x 16 m x 16 m Readout: RPCs B=1.5 T 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 G Majunder and N Mondal to report on progress INO at ideal position! 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Totally Active Scintillating Detectors (TASD) Possible improvement: Totally Active Scintillating Detector (TASD) using Nona and Minerna concepts A Bross to report at this meeting 3333 Modules (X and Y plane) Each plane contains 1000 slabs Total: 6.7M channels 15 m 100 m 3 cm 1.5 cm 15 m Momenta between 100 MeV/c to 15 GeV/c Magnetic field considered: 0.5 T Reconstructed position resolution ~ 4.5 mm Reduction threshold: access second oscillation maximum and electron identification 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Totally Active Scintillating Detectors (TASD) Neutrino CC reconstructed efficiency Muon charge mis-ID rate A. Bross will show electron identification efficiency based on “visual” scans 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Totally Active Scintillating Detectors (TASD) Main problem: magnetisation of huge volume (difficulty and cost) 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! A.Bross to update 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Totally Active Scintillating Detectors (TASD) Possible use of TASD opens up possibility of running at a low energy neutrino factory (4 GeV) Bross, Ellis, Geer, Mena, Pascoli, Li Important topic of discussion at this meeting 95% CL CP violation at 1480 km 95% CL mass hierarchy at 1480 km 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting Water Cherenkov 65m 60m MEMPHYS Water Cherenkov detector better suited for low energy options but… P.Huber and Th.Schwetz, ArXiv:0805:2019 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting Water Cherenkov Water Cherenkov simulations with MEMPHYS: Lots of progress in getting Water Cherenkov simulations up and running Tonnazo, Vassilopolous p m- g p0 2g nm(2GeV) Number PE/MeV MEMPHYS: Time residuals fitted vertex: 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting Liquid Argon TPC Different approaches for large (50-100 kton) Liquid Argon TPCs LANNDD 2001 Glacier 2003 (Europe) Flare 2004 (Fermilab, USA) Modular 2007 (Europe) Update on progress at dedicated LAr session 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

A tentative detector layout Liquid Argon TPC A tentative detector layout (GLACIER) Single detector: charge imaging, scintillation, possibly Cerenkov light Charge readout plane (LEM plane) GAr E ≈ 3 kV/cm LAr Electronic racks Extraction grid E-field E≈ 1 kV/cm Field shaping electrodes Cathode (- HV) UV & Cerenkov light readout PMTs 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Magnetised Emulsion Cloud Chamber Tau detection far detector: Emulsion detector à la OPERA: “silver channel” Is tau detection needed at far detector: can Non Standard Interactions (NSI) be determined with near detector instead? Electronic det: e/p/m separator & “Time stamp” Rohacell® plate emulsion film stainless steel plate spectrometer Shower absorber target Emulsion Cloud Chamber Muon charge misidentification Muon momentum resolution 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Beam Diagnostics and Near Detector aims Beam diagnostics (needed for flux measurement) Number of muon decays (Beam Current Transformer?) Measurement of divergence (Beam Cherenkov?) Measurement of muon polarization (tagged spectrometer?) Near detector measurements needed for neutrino oscillation systematics: Measurement of neutrino flux Extrapolation near detector flux to far detector Measurement of charm background Cross-section measurements: DIS, QES, RES scattering Other electroweak and QCD physics with near detector Search for Non Standard Interactions (NSI) by measuring taus in near detectors M Apollonio to update 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Flux Measurement at Near Detector Best possibility: Inverse Muon Decay: scattering off electrons in the near detector. Known cross-sections R Tsenov to update 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Near Detector flux used to extract Pnenm Original idea: use matrix method with Near Detector data (even if spectrum not identical in near and far detector!) to extract oscillation probability: Where: M1=matrix relating event rate and flux of ne at ND (x-section + det) M2=matrix relating event rate and flux of nm at FD (x-section + det) M=matrix relating measured ND ne rate and FD nm rate (measured!) MnOsc=matrix relating expected ne flux from ND to FD (extrapolation) Method works well but two inversions affects fit convergence Two matrix inversions! Probability of oscillation determined by matrix method under “simplistic” conditions. Need to give more realism to detector and matter effects. 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

Near Detector flux used to extract Pnenm Now we calculate in stages: ND simulated data to predict ND flux where: M1=matrix relating event rate and flux of ne at ND Extrapolate ND flux to FD: MnOsc=matrix relating ne flux from ND to FD Extract FD interaction rate: M2=matrix relating event rate and flux of nm at FD, = prob oscillation sND/E ~35%/√E No oscillations sFD/E ~55%/√E Flux from ND Hardly any change in contours from ND Assume “true” flux There is only one matrix inversion and fit to Pnenm seems to be more robust. Work on this topic stopped for 6 months due to manpower: hope to take it up again in January 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting Near Detector Design Measure charm cross-section using Impact Parameter with Si vertex detector (can also search for NSI taus) Muon chambers EM calorimeter Hadronic Calorimeter 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009 Near detector design needs to be developed further

4th Neutrino Factory International Design Study Meeting Cross section measurements Measure of cross sections in DIS, QE and RES. Coherent p Different nuclear targets: H2, D2 Nuclear effects, nuclear shadowing, reinteractions What is expected cross- section errors from MiniBoone, SciBoone, T2K, Minerva, before NUFACT? At NUFACT, with modest size targets can obtain very large statistics, but is <1% error achievable? 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting MIND and TASD R&D effort Test assumptions of simulation in test beams Build prototype TASD inside magnetic field Build prototype MIND ~2x2x4 m3 (ie. ~10-3 full MIND Important to contain m < 2 GeV Could put INO test stand in beam Technology tests: scintillator bar readout, photon detectors and electronics Dedicated parallel session on R&D 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009

4th Neutrino Factory International Design Study Meeting Conclusions MIND is still baseline detector at medium (~4000 km) distance – mass to be reviewed (50 vs 100 kton) INO could be magic baseline (7500 km) detector at NuFact in Europe (34o storage ring still an issue) Full simulation and performance still advancing TASD is particularly useful in a LENF Liquid Argon and Water Cherenkov still being considered R&D issues to be discussed at meeting Importance of Near Detector is becoming better appreciated Happy Diwali! 4th Neutrino Factory International Design Study Meeting Mumbai, 12 October 2009