Neutrino Factory Detector R&D BENE Meeting 5 July 2006 Paul Soler University of Glasgow

2 BENE Meeting CERN, 5 July 2006 Contents 1.Water Cherenkov 2.Magnetised Segmented Detectors 3.Liquid Argon TPC 4.Hybrid Emulsion Detectors 5.Beam Diagnostic Devices 6.Near Detector 7.Conclusions

3 BENE Meeting CERN, 5 July 2006 o Suitable for low energy neutrino detection (~ GeV)  Excellent   e separation 1. Water Cherenkov Electron-like Muon-like o Impossible to put a magnetic field around it, so not suitable for neutrino factory. o Baseline for beta-beams or super-beams

4 BENE Meeting CERN, 5 July 2006 o Projects around the world: Hyperkamiokande, UNO, Memphys 1. Water Cherenkov UNO/Hyperkamiokande: ~ kton 65m Water Cerenkov modules at Fréjus Fréjus CERN 130km Memphys ~440 kton

5 BENE Meeting CERN, 5 July 2006 o Projects around the world: Hyperkamiokande, UNO, Memphys 1. Water Cherenkov R&D ASICS: Charge measurement (12bits) Time measurement (1ns) Single photoelectron sensitivity High counting rate capability (target 100 MHz) Large area pixellised PM : “PMm 2 ” 16 low cost PMs Centralized ASIC for DAQ Variable gain to have only one HV Multichannel readout Gain adjustment to compensate non uniformity Subsequent versions of OPERA_ROC ASICs aim at 200 euros/channel PMT R&D: taken charge by IPNO With PHOTONIS tests of PMT 8”, 9”  12” and Hybrid-PMT and HPD

6 BENE Meeting CERN, 5 July Water Cherenkov o Energy resolution (Mezzetto) o Memphys plan:

7 BENE Meeting CERN, 5 July Magnetised Segmented Detectors o Golden channel signature: “wrong-sign” muons in magnetised calorimeter o Baseline technology for a far detector at a neutrino factory o Issues: electron ID, segmentation, readout technology (RPC or scintillator?) – need R&D to resolve these o Technology is well understood, R&D needed to determine details, natural progression from MINOS o Magnetisation of volume seems to be most challenging problem 8xMINOS (5.4 KT) iron (4 cm) + scintillators (1cm) beam 20 m B=1 T 40KT

8 BENE Meeting CERN, 5 July Magnetised Segmented Detectors o Magnetic Iron Detector Optimised for small  13 Strong cut on muon momentum > 5 GeV/c Problems below muon momentum < 3 GeV/c (cannot see second maximum) Main background: production of charm   Q t =P  sin 2 

9 BENE Meeting CERN, 5 July Magnetised Segmented Detectors  Compromise between Large Magnetic Detector and No a concepts? o Iron free regions: improve momentum and charge determination Iron (4cm) + active (1cm) air + active (1cm) hadron shower muon 1m o Combining No a and iron-free regions ? Iron (2cm) + active (4cm) air + active (1cm) hadron shower muon Liquid scintillator iron

10 BENE Meeting CERN, 5 July Magnetised Segmented Detectors Simulation of a magnetised scintillating detector using No a and Miner a concepts with Geant4 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 Three lepton momenta: –“Low”: 100 MeV/c – 500 MeV/c initial momentum –“Medium”: 500 MeV/c – 2.5 GeV/c initial momentum –“High”: 2.5 GeV/c – 12.5 GeV/c initial momentum 0.15 T magnetic field 0.30 T magnetic field 0.45 T magnetic field o Three fields studied: Ellis, Bross

11 BENE Meeting CERN, 5 July Magnetised Segmented Detectors Position resolution ~ 4.5 mm Red Red: 0.15 T Magnetic Field Green Green: 0.30 T Magnetic Field Blue Blue: 0.45 T Magnetic Field Muon reconstructed efficiency

12 BENE Meeting CERN, 5 July Magnetised Segmented Detectors 10 solenoids next to each other. Horizontal field perpendicular to beam Each: 750 turns, 4500 amps, 0.2 Tesla. 42 MJoules. Total: 420 MJoules (CMS: 2700 MJoules) Coil: Aluminium (Alain: LN2 cooled). Possible magnet schemes for MSD Camilleri, Bross, Strolin Steel 15 m x 15 m x 15m solenoid modules; B = 0.5 T Magnet Magnet cost extrapolation formulas: Use stored energy – 14M$/module Use magnetic volume – 60M$/module GEM magnet extrapolation – 69 M$/module x10 modules!

13 BENE Meeting CERN, 5 July Liquid Argon TPC  Liquid argon detector is the ultimate detector for e and  appearance (“silver channel”). Simultaneous fit to all wrong and right sign distributions. o ICARUS has constructed 600 t modules and observed images o Main issues: inclusion of a magnetic field, scalability to ~ kT

14 BENE Meeting CERN, 5 July Liquid Argon TPC LAr Cathode (- HV) E-field Extraction grid Charge readout plane (LEM plane) UV & Cerenkov light readout PMTs E≈ 1 kV/cm E ≈ 3 kV/cm Electronic racks Field shaping electrodes GAr A tentative detector layout Very ambitious!! Single detector: charge imaging, scintillation, possibly Cerenkov light Magnetic field problem not solved Max field 0.4 T

15 BENE Meeting CERN, 5 July Liquid Argon TPC o Charge readout with Large Electron Multiplier (LEM) o Light readout with Wavelength Shifting (WLS) coated PMT o Drift very high voltage: Greinacher circuit o Liquid argon production (local plant ~50 kton/year) and purification o Very long drift lengths: 5-20 m Very large Liquid Argon R&D issues: o Set up test beam with magnet at East area from the CERN PS

16 BENE Meeting CERN, 5 July Hybrid Emulsion Detectors Plastic base Pb Emulsion layers  1 mm  Emulsion detector for  appearance, a la OPERA  Issues: high rate, selected by choosing only “wrong sign”  →  events o Assume a factor of two bigger than OPERA (~4 kt)

17 BENE Meeting CERN, 5 July Hybrid Emulsion Detectors Electronic det: e/  separator & “Time stamp” Rohacell® plate emulsion film stainless steel plate spectrometertargetshower absorber Muon momentum resolution Muon charge misidentification

18 BENE Meeting CERN, 5 July Hybrid Emulsion Detectors o Transverse dimension of a plane: 15.7x15.7 m 2 (as in Nova) o 1 brick: 35 stainless steel plates 1 mm thick (2 X 0,, 3.5 kg) o Spectrometer: 3 gaps (3 cm each) and 4 emulsion films o A wall contains bricks  Weight = 68 tons o For 60 walls  bricks  4.1 kton o Emulsion film: 47,328,000 pieces (in OPERA there are 12,000,000) o Electronic detector: 35 Nova planes (corresponding to 5.3 X 0 ) after each MECC wall  2100 planes o Total length of detector is: ~ 150 m Possible design hybrid emulsion-scintillator far detector Synergy emulsion-magnetic scintillation detector Golden and silver channels simultaneously!

19 BENE Meeting CERN, 5 July Beam Diagnostic Detectors o Beam Current Transformer (BCT) to be included at entrance of straight section: large diameter, with accuracy ~ o Beam Cherenkov for divergence measurement? Could affect quality of beam. storage ring shielding the leptonic detector the charm and DIS detector Polarimeter Cherenkov BCT

20 BENE Meeting CERN, 5 July Beam Diagnostic Detectors o Muon polarization: Build prototype of polarimeter Fourier transform of muon energy spectrum amplitude=> polarization frequency => energy decay => energy spread.

21 BENE Meeting CERN, 5 July 2006 o Near detectors should be able to measure flux and energy of and o Calibration and flux control: o High event rate: ~10 9 CC events/year in 50 kg detector 6. Near detector o Measure charm in near detector to control systematics of far detector (main background in oscillation search is wrong sign muon from charm) o Other physics: neutrino cross-sections, PDF, electroweak measurements,... o Possible technology: fully instrumented silicon target in a magnetic detector. What needs to be measured

22 BENE Meeting CERN, 5 July Near detector Energy spectra for muons from reaction (green) and (blue) o Energy spectrums for muons from reaction (green) and (blue)

23 BENE Meeting CERN, 5 July Near detector Muon chambers EM calorimeter Hadronic Calorimeter Possible design near detector around UA1/NOMAD/T2K magnet

24 BENE Meeting CERN, 5 July Near detector o Vertex detector ̶ Identification of charm by impact parameter signature ̶ Demonstration of charm measurement with silicon detector: NOMAD-STAR o Impact parameter resolution Pull:  ~1.02  x ~33  m

25 BENE Meeting CERN, 5 July Near detector o Efficiency very low: 3.5% for D 0, D + and 12.7% for D s + detection because fiducial volume very small (72cmx36cmx15cm), only 5 layers and only one projection. o From 10 9 CC events/yr, about 3.1x10 6 charm events, but efficiencies can be improved with 2D space points (ie. Pixels) and more measurement planes  For example: 52 kg mass can be provided by 18 layers of Si 500  m thick, 50 x 50 cm 2 (ie. 4.5 m 2 Si) and 15 layers of B 4 C, 5 mm thick (~0.4 X 0 )  Fully pixelated detector with pixel size: 50  m x 400  m  200 M pixels  Double sided silicon strips, long ladders: 50 cm x 50  m  360 k pixels

26 BENE Meeting CERN, 5 July Near detector oR&D programme 1)Vertex detector options: hybrid pixels, monolithic pixels (ie. CCD, Monolithic Active Pixels MAPS or DEPFET) or strips. Synergy with other fields such as Linear Collider Flavour Identification (LCFI) collaboration. 2)Tracking: gas TPC (is it fast enough?), scintillation tracker (same composition as far detector), drift chambers?, cathode strips?, liquid argon (if far detector is LAr), … 3)Particle identification: dE/dx, Cherenkov devices such as Babar DIRC?, Transition Radiation Tracker? 4)Calorimetry: lead glass, CsI crystals?, sampling calorimeter? 5)Magnet: UA1/NOMAD/T2K magnet?, dipole or other geometry? oCollaboration with theorists to determine physics measurements to be carried out in near detector and to minimise systematic errors in cross- sections, etc.

27 BENE Meeting CERN, 5 July 2006 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

28 BENE Meeting CERN, 5 July Total Detector R&D Programme No information yet

29 BENE Meeting CERN, 5 July 2006 Conclusions  Baseline detector technologies: ̶ Water Cherenkov detector for low energy Super-beams and Beta-beams ̶ Segmented Magnetic Detectors for far detector at a Neutrino Factory for golden channel  Other far detector options include: ̶ Emulsion Cloud Chamber for silver channel. Can be interspersed within Segmented Magnetic Detector ̶ Liquid Argon TPC. This detector inside a magnetic field could potentially do everything, but some R&D issues still need to be addressed  Ideas for beam diagnostics and near detectors are being developed  Test beam facility for Neutrino detector R&D needed  Neutrino detector R&D programme over next 4 years could total ~10 MEuro (without Water Cherenkov detector R&D).