Chang Kee Jung August 2007, LP07 Planning the Future Neutrino Projects in Global Context: Ideas, Challenges, and Limitations Planning the Future Neutrino Projects in Global Context: Ideas, Challenges, and Limitations Chang Kee Jung Stony Brook University Lepton-Photon Symposium Daegu, Korea, August 17, 2007 Lepton-Photon Symposium Daegu, Korea, August 17, 2007 Thanks to: H. Aihara, A. Blondel, D. Finley, T. Kajita, Y.-K. Kim, K. Nakamura, L. Oberauer and A. Rubbia

Chang Kee Jung August 2007, LP Neutrino Revolution and Physics Goals for NNN Experiments Neutrino Oscillations Super-Kamiokande+Atm exps +SNO+Solar exps+Kamland Non-zero but tiny Neutrino Mass (See-saw Mechanism?) (Grand) Unification Proton Decay Large Underground Detectors Lepton Mixing Matrix K2K, MINOS, CNGS, T2K, NOvA Reactors, Superbeams, Betabeams Non-zero Neutrino Mixing CP Violation in Lepton Sector Superbeam, Betabeams, Neutrino Factories LMA solution, sin  13 ≠ 0 Lepto-Genesis Matter-antimatter Asymmetry in the Universe Majorana Phase Supernova ’s Dirac Phase

Chang Kee Jung August 2007, LP07 Remaining Questions/Tasks in Neutrino Physics What we need to measure/observe further: –Remaining oscillation parameters:  13 ; remaining sign of  m 2 (m m 2 2 ); CP violating (Dirac) phase   23 = 45?  13 = 0? (underlying symmetry?) –      a  –Determine Dirac vs. Majorana nature of neutrino –Neutrinos from galactic supernova explosion –Neutrinos from astrophysical point sources (AGN, GRB, etc…) –relic neutrinos (from past supernova and from Big-Bang)

Chang Kee Jung August 2007, LP07 Physics Beyond SuperK, T2K, NOVA Requires a Next generation Nucleon decay and Neutrino (NNN) experiments with physics sensitivities an order of magnitude better than those of SuperK, T2K and NOVA –by the time a NNN Detector is built, SuperK will have accumulated more than 20 years of data for non-accelerator physics topics and T2k will have accumulated more than 10 years of the data. To get there, –increase statistics  neutrino flux:Superbeam (1MW ~ 4MW)  target (detector) mass:WC (~500kt FV), LAr (~100kt) –improve signal detection efficiencyLAr (~80%) –reduce backgrounds    backgroundOff-axis, LAr  intrinsic beam e neutrino factory, beta-beam –utilize multiple oscillation peaksWide-band beam –resolve mass hierarchyvery long baseline (>1000 km)

Chang Kee Jung August 2007, LP07 Wide-band Beam for Very Long Baseline Neutrino Oscillation Experimnet W. Marciano (hep-ph/ ) P  ’  sin 2 (1.27  m 2 L/E) –Look for oscillation effect on 2nd, 3rd … peaks –Sensitivity to CPV ~ independent of baseline –Allow very long baseline superbeam experiment Wideband Beam w/ very long baseline (L > ~1000 km) –observation of multiple peaks in the neutrino energy spectrum each with different manifestation of matter effect and CPV –Energy dependence lifts degeneracy (in Off-axis scheme) –Long baseline enhances matter effect –However, in this scheme   background from high energy component needs to be controlled

Chang Kee Jung August 2007, LP07 Future Large Neutrino Project Ideas Water CherenkovLiquid Argon Liquid Scintillator Iron Cal/Tracker Superbeam (1MW~4MW) HyperK/T2KK MEMPHYS UNO, 3M MODURAr, GLACIER LANDD, LArTPC TASD Factory GLACIER LANDD TASD MIND INO  -beam MEMPHYSGLACIER LENA TASD Yellow: Asia, Red: Europe, Green: U.S. (The list is not complete.) Most of these detectors are multi-purpose detectors when built deep underground (Proton decay searches, Supernova (relic) neutrino detections, Atmospheric and Solar neutrinos, etc. as well as LBL neutrino oscillation experiments) Far Detector Types Neutrino Beam Source

Chang Kee Jung August 2007, LP07 Next Generation Water Cherenkov Detectors UNO (1999) DUE Hyper-Kamiokande (1999) MEMPHIS (2002) DIECI 3M (2001) TRE

Chang Kee Jung August 2007, LP07 Challenges and Limitations w/ Large WC Detectors Mature technology –~ 3 decades of real experiment experience Reasonable extrapolation from the current experiments (10~20)  no critical path R&D item  Ready to be built (R&D needed mostly to reduce cost) Challenges –difficult to get the national lab detector development types excited  “It is a dumb detector! It is not sexy!” –civil engineering: construction of a very large cavity, deep underground  It is sexy to rock engineers –cost reduction Large Photo-detector R&D –Hybrid Avalanche Photo Detector (HAPD) by U. of Tokyo & Hamamatsu –Low cost mass-production R&D by Photonis

Chang Kee Jung August 2007, LP07 Hybrid Avalanche Photo Detector (HAPD) R&D by U. of Tokyo and Hamamatsu It will be interesting to see the overall improvement in the detector performance w/ new detector simulation  better vertex and energy resolution? Hope for a factor of four reduction in the cost  If Achieved, revolutionary!! H. Aihara 13” HAPD

Chang Kee Jung August 2007, LP07 Perlite insulation  ≈70 m h =20 m Electronic crates ICARUS (since 1985) LArTPC (since 2005) GLACIER (since 2003) LANND (since 2001) MODULAR (since 2007)  ICARUS 1985  LANND 2001  GLACIER 2003  LArTPC 2005  MODULAR 2007 Liquid Argon Detectors

Chang Kee Jung August 2007, LP07 Detector must be BIG (~100 kton) to be competitive with other technologies –need to extrapolate the technology from 300 ton to 100 kton (300)  success of ICARUS (physics output) or other 1kton class detector is critical It will provide a base for extrapolation (physics reach, cost, safety, etc.) Drift lengths of several meters are necessary Construction of tank, underground Outstanding Issues to be addressed –Dewar technology –Safety & environmental issues –Argon and purification system –Drift High Voltage system –Charge readout methods & Electronics –Cost reduction per unit mass Different Approaches –a modular or a scalable detector –evacuable or non-evacuable dewars –detect ionization charge in LAr without amplification or with amplification LNG Storage Tank Challenges and Limitations with Large LAr TPC

Chang Kee Jung August 2007, LP07 Large Liquid Scintillator Detector Low Energy Neutrino Astronomy Total (Fiducial) vol.: 50 (22) kton Scintillator: PXE (~12 m light attenuation nm) 13,500 20” PMTs (30% coverage) ~110 pe/MeV R&D total ( ): 1.45 MEuro funded Challenges and Limitations – Idea/R&D stage but mature technology  extrapolation not unreasonable (~1kton  ~50 kton) (50) – Development of liquid scintillator with desired properties  Light yield, timing, light absorption and scattering length, etc.  Purification needs and possibilities  Long term property – Environmental concern, and cost and availability of the scintillator LENA

Chang Kee Jung August 2007, LP07 FNAL 1315 km 1500 km Homestake (WB) Henderson (WB) Possible Long Baseline Neutrino Oscillation Experiments in U.S. Measure  ,  CP and sign of  m   Ash River (12 km OA, LAr, surface) Project X 2MW (ask Young-Kee) 810 km

Chang Kee Jung August 2007, LP07 HyperK and T2KK Possible Sites Super-K (Depth:2700mwe) Hyper-K (Depth: 1400 – 1900mwe, not decided yet ) (Tochibora-mine of the Kamioka mining company) J-PARC 295km T2KK (more matter effect, less ambiguities) JPARC 075  4MW Off-axis angle 2.5deg.off-axis 2.5 deg. off axis (or smaller off-axis Angle) 2.5 deg. off axis (or smaller off-axis Angle)

Chang Kee Jung August 2007, LP07 Neutrino Factory Neutrino Factory International Scoping Study « baseline » Major Challenges –very little “established accelerator practice” –4MW on target –phase rotation and cooling inside solenoid  operation of high gradient RF in magnetic field –fast acceleration of large emittance beams: RLAs, FFAG Several on-going R&D program First Step towards a Muon Collider Fixed-Field Alternating-Gradient pure  e,  — pure  , e —

Chang Kee Jung August 2007, LP07 Beta Beam CERN-based EURISOL Design Study PS Decay Ring ISOL target & Ion source SPL Cyclotrons, linac or FFAG Decay ring B = 5 T L ss = 2500 m SPS ECR Rapid cycling synchrotron Nuclear Physics Same detectors as Superbeam ! production and target Stacking neutrinos of E max =~600MeV activation pure  e, e —

Chang Kee Jung August 2007, LP07 Challenges w/ the  -beam and Sensitivity Comparison Challenges w/ the  -beam –18Ne production difficult so far  too low by factor 24 –Ion losses are ~30%  the limit in SPS –Low energy neutrino beam  250 MeV near nuclear effect regime However, it looks easier than a neutrino factory! Sensitivity Comparison

Chang Kee Jung August 2007, LP07 Possible Neutrino Beams in Europe Fréjus Current tunnel New safety tunnel 130 km Superbeam  -beam CERN to India -factory beam

Chang Kee Jung August 2007, LP07 Global Outlook Double Chooz 3 years ~0.05 (3  C.L.) NO A ~2017 ~0.01 (3  C.L.) Approved ExperimentsSuperbeam Neutrino Factory  -beam Chooz Excluded ~0.15 (90%  C.L.) T2K 5 years ~0.008 (90%  C.L.) Daya Bay 3 years ~0.02 (3  C.L.) If sin 2 2  13 > ~0.1, modest improvement of current experiments for CPV, expect a global race to measure CPV, a careful plan to resolve mass ordering needed If sin 2 2  13 > ~0.01, requires a superbeam experiment for CPV, a long baseline (>1000km) for mass ordering If sin 2 2  13 < ~0.01, requires a neutrino factory experiment sin 2 2  13

Chang Kee Jung August 2007, LP07 Global Planning Ideally, decision after the ILC decision (especially site) around 2010 – keep regional balance and vitality of the particle physics in each region – If so, who guides the international dialog and who makes the decision? (ICFA, PANAGIC, or a New IUPAP committee on Neutrino Physics?) –but, should not wait for ILC decision forever (decision ~2012)  neutrino community could make a decision for the ILC community!! However, the cost of the neutrino projects are modest enough for single regional effort (a la J-PARC, TeVatron, B-factories...) w/ modest international participation We should assume at least one of the superbeam experiments and neutrino factory experiments will be performed eventually – the current approved experiments will not likely make precision measurements of sin 2 2  13 Thus, there should be serious effort to support various machine and detector R&D Avoid too many if’s (conditions), which will effectively kill the field

Chang Kee Jung August 2007, LP07 Common Denominator Race to Higher Proton Beam Power (2 to 4 MW) –applications to neutrino superbeam, neutrino factory, ILC, nuclear physics, etc.  Europe: CERN 4MW SPL  Japan: J-PARC Upgrade  US: Project X at Fermilab

Chang Kee Jung August 2007, LP07 International Collaboration and Coordination Next generation Nucleon decay and Neutrino (NNN) detectors Workshop Series –concentrate on the next generation detector ideas and R&D –NNN07-Hamamatus, Oct. 2-5, 2007 Neutrino Factory Workshop Series –NuFact07-Okayama, Aug. 6-11, 2007 LAGUNA (Large Apparatus for Grand Unification and Neutrino Astrophysics) –European R&D proposal for Large Liquid Detectors  MEMPHYS, GLACIER, LENA  decision expected, September 2007 International Scoping Study (ISS) –European led effort to study feasibility of future neutrino projects

Chang Kee Jung August 2007, LP07 Final Comments Non-zero neutrino mass is the only indication for physics beyond the Standard Model –(Grand) Unification? Proton decay? Diverse experiments w/ plausible extrapolation of the existing technology are proposed for measuring sin 2 2  13, CPV and mass ordering in lepton sector (down to sin 2 2  13 ~0.01) –Important physics goals! Measurements must be done! Multi-purpose nature of the projects –proton driver (2 ~ 4MW): superbeam, neutrino factory, ILC, etc. –large underground detectors: proton decay, neutrinos from astrophysical sources, etc. Incremental approach is easier to implement –However, existing constraints can prohibit optimization –sometimes completely new approach, new machine and new detector are more efficient way to do desired physics

Chang Kee Jung August 2007, LP07 The End