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ISS-detectors. Working group reports. Water Cerenkov Detectors report by Jacques Bouchez Magnetic Sampling Detectors http://dpnc.unige.ch/users/blondel/detectors/magneticdetector/SMD-web.htm report by Alan Bross Liquid Argon TPC http://www.hep.yorku.ca/menary/ISS/
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Working group reports Water Cerenkov Detectors report by Jacques Bouchez Magnetic Sampling Detectors http://dpnc.unige.ch/users/blondel/detectors/magneticdetector/SMD-web.htm report by Alan Bross Liquid Argon TPC http://www.hep.yorku.ca/menary/ISS/ reports by Scott Menary, Andreas Badertscher Emulsion Detectors http://people.na.infn.it/~pmiglioz/ISS-ECC-G/ISSMainPage.html report by Pasquale Migliozzi Near Detectors http://ppewww.ph.gla.ac.uk/~psoler/ISS/ISS_Near_Detector.html reports by Paul Soler and Federico Sanchez Detector Technology will take place this afternoon
Technology discussion session (organized by Alan Bross and Kenji Kaneyuki) Wednesday 25 January time speaker 14:00 MPPC T. Nakadaira 14 :30 SiPMs for T2K ND280 Y. Kudenko 15:00 New VLPC R&D A.Bross 15:30 Hybrid PMT H. Nakayama 16:00 Scintillating Fiber Production (Kuraray) Y. Shiomi 16:30 Open discussion
The MEMPHYS Project 65m CERN 65m 130km Fréjus 4800mwe Water Cerenkov modules at Fréjus CERN to Fréjus Neutrino Super-beam and Beta-beam Excavation engineering pre-study has been done for 5 shafts
A Very Large Laboratory In the middle of the Fréjus tunnel at a depth of4800 m.w.e a preliminary investigation shows the feasibility to excavate up to five shafts of about 250,000 m3 each HK Henderson
Detector basic unit each cavity 70 m diameter and 80 m total height Detector: cylinder (a la SK) 65 m diameter and 65 m height: : → 215 000 tons of water (4 times SK) taking out 4 m from outside for veto and fiducial cut →146 000 ton fiducial target 3 modules : 440 kilotons (like UNO) BASELINE 4 modules would give 580 kilotons (HK) →Simulations done using 440 kt 65m 65m ~ 4 x SK
R&D on electronics (ASICs) Integrated readout : “digital PM (bits out)” Charge measurement (12bits) Time measurement (1ns) Single photoelectron sensitivity High counting rate capability (target 100 MHz) Large area pixellised PM : “PMm2” 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
Mechanics & PMT tests Taken in charge by IPNO: well experienced in photodetectors (last operation: Auger). With PHOTONIS tests of PMT8”, 9” 12” and Hybrid-PMT and HPD Electronic box water tight Basic unit that we want to build and test under water IPNO
Year 2005 2010 2015 2020 Safety tunnel Excavation Lab cavity P.S Study Excavation detector PM R&D PMT production Outside lab. Installation Det.preparation P-decay, SN Non-acc.physics Superbeam Construction Superbeam betabeam Construction Beta beam A possible schedule for MEMPHYS at Frejus decision for cavity digging decision for SPL construction decision for EURISOL site
Superbeam + beta beam together 2 beams 1 detector SUPERBEAMBETABEAM nm→ ne ne → nm nm → ne ne → nm 4 n flavours + K pure 2yrs 5yrs p+/p- 8yrs 5yrs 2 ways of testing CP, T and CPT : redundancy and check of systematics
MEMPHYS comments (AB) -- French neutrino community strongly motivated -- R&D already started. -- CERN beams (Beta-beam, Superbeam) possible please consider oscillation physics performance with BOTH betabeam gamma=100 AND WBB Superbeam Ep= 3-4 GeV. (no Kaons) ball-park est. cost of total package 600M€ (detector) + + (from erlier est…) betabeam (~500M€) + superbeam (~400 M€) main physics question mark: is it possible at all to do the physics with low energy events ? J. Bouchez promised to investigate the principle of a near detector system to determine cross-sections and efficiencies for the four flavours of neutrinos as function of energy.
considerable noise reduction can be obtained by gas amplification
industrial study of large Tank 70 m diameter, 20 m drift = 100 kton of Larg shown to be feasible conceptually
height is limited by high voltage 1kV/cm 2 MV for 20m… field degrader in liquid argon tested (Cockroft-Greinacher circuit)
and drift under high pressure in pressurized cryostat long drift will be tested in 5m vertical drift tube (ETHZ-Napoli)
consequences of long drift: time integration • Detector must be underground to limit cosmics (are they all just muons?) • photomultipliers sensitive to 128 nm scintillation light can be installed for trigger • however Raleigh scattering (<1m scattering length) limits position reconstruction from light timing • it is possible to tag timing of neutrino events with precision small wrt 100 ns. and operate with both mu+ and mu- trains injected in storage ring
l Muons of both signs circulate in opposite directions in the same ring. The two straight sections point to the same far detector(s). OK There is one inconvenient with this: the fact that there are two decay lines implies two near detectors. In addition this does not work for the triangle. this can be solved by dog bone or two rings with one or more common straights l- l+ m+m- d ex: race track geometry: constraint: ¦l- - l+¦ > l + d where d is the precision of the experiments time tag plus margin
NB B field is perp. to drift! NBB: what range of electrons does this correcpond to?
Questions: what is efficiency as a function of energy vs B field? what magnetic field is necessary to have reasonable efficiency for electrons up to first oscillation maximum and a little more? (this is of course a baseline dependent statement) phenomenologists: be prepared to add this to the perfect detector! 10 (100?) kton with 30% efficiency for wrong sign electrons up to 5 GeV ? dreams? High Tc supra conductor magnet?
US Larg effort (Menary) Implementation of Larg detector in Globes underway a few weeks to go!
An ideal detector exploiting a Neutrino Factory should: Identify and measure the charge of the muon (“golden channel”) with high accuracy Identify and measure the charge of the electron with high accuracy (“time reversal of the golden channel”) Identify the decays (“silver channel”) Measure the complete kinematics of an event in order to increase the signal/back ratio Migliozzi
“MECC” structure B DONUT/OPERA type target + Emulsion spectrometer + TT + Electron/pi discriminator 3 cm Stainless steel or Lead Film Rohacell Electronic detectors/ECC Assumption: accuracy of film by film alignment = 10 micron (conservative) 13 lead plates (~2.5 X0) + 4 spacers (2 cm gap) (NB in the future we plan to study stainless steel as well. May be it will be the baseline solution: lighter target) The geometry of the MECC is being optimized
q-mis vs zvertex the real question will be how many right signs appear as wrong sign! Given the true-hit based reconstruction, the quoted charge misidentification can be seen as an lower limit. Anyhow it is a good starting point!
Muon 3 GeV/c
100 m 3. Flux normalisation (cont.) • Rates: • Em = 50 GeV • L = 100 m, d = 30 m • Muon decays per year: 1020 • Divergence = 0.1 mm/Em • Radius R=50 cm E.g. at 25 GeV, number neutrino interactions per year is: 20 x 106 per 100 g/cm2. With 50 kg 109n interactions/yr High granularity in inner region that subtends to far detector. Yearly event rates
3. Flux normalisation (cont.) • Neutrino flux normalisation by measuring: • Signal: low angle forward going muon with no recoil • Calculable with high precision in SM • Same type of detector needed for elastic scattering on electrons: E.g. CHARM II obtained value of sin2qW from this
4. Muon polarization • Fit neutrino spectrum for polarization: Compare fitted polarization to measured one from polarimeter:
5. Cross sections • Measurement of cross sections in DIS, QE and RES. • Coherent p • Different nuclear targets: H2, D2 • Nuclear effects, nuclear shadowing, reinteractions • With modest size targets can obtain very large statistics • What is lowest energy we can achieve? E.g. with LAr can go down to ~MeV
threshold will be different for e and mu, affected by fermi motion, reinteractions and Q2 distribution (neutrino antineutrino)