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The Last Unknown Neutrino Mixing Angle:  13

?. reactor and accelerator. atmospheric, K2K. SNO, solar SK, KamLAND. 0.  13 = ?.  23 = ~ 45°.  12 ~ 32°. The Last Unknown Neutrino Mixing Angle:  13. ?. U MNSP Matrix Maki, Nakagawa, Sakata, Pontecorvo. What is  e fraction of  3 ?

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The Last Unknown Neutrino Mixing Angle:  13

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  1. ? reactor and accelerator atmospheric, K2K SNO, solar SK, KamLAND 0 13 = ? 23 = ~ 45° 12 ~ 32° The Last Unknown Neutrino Mixing Angle: 13 ? UMNSP Matrix Maki, Nakagawa, Sakata, Pontecorvo What ise fraction of 3? Is there  symmetry in neutrino mixing?

  2. 13 m213≈m223 detector 1 Pee Pee detector 2 nuclear reactor Distance (km) Measuring 13 with Reactor Neutrinos Search for 13 in oscillation experiment Ue3 ~1.8 km ~ 0.3-0.5 km Pure measurement of 13. Daya Bay, China

  3. 1. Search and discovery of 3 0 - key in understanding neutrino mixing and prospects for CP searches 2. Precise measurement of sin223 13 and 23 are 2 of the 26 parameters of the SM, worthy of precision measurements  resolves 23 degeneracy 3. Complimentarity with accelerator experiments  together reactor + accelerator experiments (NOvA, T2K) provide early indication of mass hierarchy and perhaps CP Measuring 13 at Daya Bay Reactor 3 experiment sets the scale for future accelerator-based oscillation measurements Ref: hep-ex/0409028

  4. acc appearance acc dis/appearance acc disappearance reactor + acc dis/appearance reactor Ref: hep-ph/0601258 Resolving the23 Parameter Ambiguity approximately, Super-K, T2K disappearance 23 = 45±9° NOvA, T2K eappearance P[e]

  5. mass hierarchy CP violation matter 13 from Reactor and Accelerator Experiments reactor (e disappearance) - Clean measurement of 13 - No matter effects accelerator (e appearance)  sin2213 is missing key parameter for any measurement of CP

  6. hep-ex/0409028 Future of Neutrino Oscillation Physics: Next 10 Years Reactor measurement of 13 Constraining CP in combined analysis Accelerator neutrino studies of nm ne

  7. The Daya Bay Nuclear Power Facilities • Powerful facilities with total • thermal power: • 11.6 GW (now)17.4 GW (2011) • Adjacent to mountain, easy to • construct tunnels to underground • labs with sufficient overburden to • suppress cosmic rays LingAo II NPP: 2  2.9 GWth Ready by 2010-2011 LingAo NPP: 2  2.9 GWth 1 GWthgenerates 2 × 1020 ne per sec Daya Bay NPP: 2  2.9 GWth

  8. Far site 1600 m from Lingao 2000 m from Daya Overburden: 350 m Empty detectors are moved to underground halls through an access tunnel. Filled detectors can be swapped between the underground halls via the horizontal tunnels. Ling Ao Near 500 m from Lingao Overburden: 98 m Mid site ~1000 m from Daya Overburden: 208 m Ling Ao-ll NPP (under const.) 230 m (15% slope) 810 m 292 m (8% slope) Ling Ao NPP Daya Bay Near 360 m from Daya Bay Overburden: 97 m Entrance portal Daya Bay NPP Total length: ~3000 m

  9. Geotechnical Survey Geophysical survey: probe subsurface structure Topographical survey: produce high-resolution topographic maps far Lingao near mid Lingao near mid Borehole drilling Daya near

  10. Chris Laughton (FNAL) Pat Dobson (LBL) Joe Wang (LBL) Yanjun Sheng (IGG) Findings of Geotechnical Survey • No active or large fault • Earthquake is infrequent • Rock structure: massive and blocky granite • Rock mass: most is slightly weathered or fresh • Groundwater: poor flow at the depth of the tunnel • Quality of rock mass: stable and hard US experts in geology and tunnel construction assist geotechnical survey: Good geotechnical conditions for tunnel construction

  11. The US should mount one multi-detector reactor experiment sensitive to nedisappearance down to sin22θ13 ~ 0.01.

  12. Sin22q13 < 0.01 • Achieve high statistical precision: • Utilize multiple reactor cores (4→6) effectively • At least 80 Tons at far site • Control Systematic errors: • Utilize multiple detectors at different baselines • – measure RATIOS • Reactor power fluctuations – optimally combine ratios • Make detectors as IDENTICAL as possible Science Goals → Experiment Design → R&D

  13. Science Goals → Experiment Design → R&D • Reduce and control systematic errors: • “Identical” detectors at multiple sites • → detector design/construction, side-by-side comparisons • Detector performance - well-understood, stable • → materials/construction, calibration/monitoring • Reduce radioactivity background • → materials/construction, Gd-loaded scintillator • Reduce and measure cosmogenic backgrounds • →shielding, muon veto and tracking, DAQ system • Swap detectors • → horizontal tunnel system, locomotion equipment US R&D tasks focused on achieving these goals

  14. 20t Gd-doped LS buffer Antineutrino Detector • First priority is to define interfaces with other systems: • Interface with cavern/tunnels • define lifting and support structures • define transport fixtures • understand detector environment (water, air) • Interface with calibration system • specify penetrations into detector • detector environment has significant influence • on this interface • Antineutrino detector specifications: • Acrylic vessel thickness, transparency, compatibility with liquid scintillator • Surface reflectors, PMT configuration • Implications of moving detectors gamma catcher

  15. History of BNL R&D on Metal-loaded LS, M-LS • Dilute (<<1%) Gd in LS had been successfully used to detect neutrons in many relatively short-term nuclear-physics experiments. • However, prospects were dim to prepare high concentrations of M-LS (~10% Yb, In, or Nd) for years-long solar-neutrino (LENS) and  experiments (SNOLab). • In 2002-05, we at BNL developed new chemical methods to solve these problems, following approach from radiochemistry and nuclear-fuel reprocessing. • We successfully applied our methods to make suitable ~0.1% Gd in PC (the LS) that avoided the chemical/optical degradation problems encountered in the Chooz and Palo Verde experiments. • Our current R&D is with a new LS, Linear Alkyl Benzene, LAB. • LAB is attractive alternative to PC. It is biodegradable, has high flashpoint, and tons of it are produced by industry.

  16. Optical Attenuation of BNL Gd-LS, Stable so far for ~500 days Gd-LS under UV light (in 10 cm cells)

  17. Performance of Gd in PC and LAB Optical Spectra Light Output Spectra • Have ~1% Gd in 100% LAB and 100% PC. Will use ~0.1% Gd in 13 experiment. • The LAB has lower optical absorption, longer attenuation length, better chemical and ESH properties. • LAB and PC have very similar light output efficiency

  18. Active Water Shield and Muon Tracker • Specifications • Two meters plus of purified water surrounding the neutrino detector modules to suppress ambient radioactivity background • Water pool equipped with PMTs to detect muons via their Cherenkov light with >95% efficiency • High efficiency (>95%) muon tracker; less than 0.3% inefficiency when combined with the muon water Cherenkov • Good (ns) timing resolution to reduce accidentals due to ambient radioactivity background • Muon tracker can be deployed in water pool or outside water tank • Robust, good long-term stability

  19. Far Hall Detector Configuration Top vetoes

  20. Veto Configuration

  21. Muon Tracker • Scintillator strip muon tracker • Proven technology used in MINOS, OPERA and elsewhere • Not necessary to exceed performance of extant systems! • 10 cm x 1 cm x 7.5 m plastic scintillator strips co-extruded with reflective TiO2 on the outside • Scintillation light read out by wavelength shifting (wls) fibers embedded in strips • Fibers read out by multi-anode PMTs at both ends • High level of readout multiplexing possible since muon events have low occupancy • Two layers lining 5 sides of water pool or outside water tank provide good 2-d tracking of through-going muons • Two or three layers on top to provide redundancy on stopping muons. • Total area of the muon tracker is about 5100 m2

  22. Opera target tracker Scintillator strips 6.86 m x 26.3 mm x10.6 mm read out by WLS fibers coupled to PMTs on both ends

  23. Opera tracker performance Four p.e./MIP at the far end, so 2-end requirement highly efficient

  24. Active Water Shield and Muon Tracker • Alternate/Backup muon tracker technologies • Resistive Plate Chambers: • Gas detectors read out by external pick-up strips (for water tank option only) • Least expensive option but efficiency susceptible to environmental parameters, especially pressure and gas purity • Liquid Scintillator Modules: • 50 cm x 5 cm x 7.5 m liquid scintillator modules read out via wls at both ends by single-anode PMTs. • 5 cm thick modules allows rejection of ambient radioactivity background based on pulse height • One layer inside water pool or outside water tank and on top • Cheaper than plastic strips, but mechanically more complex

  25. 96- 98% RPC IHEP BESIII RPC

  26. LS Module Module cross section: or 50 40 30 20 10 0 Performance scaled from NOvA proposal ~10 p.e. at far end (7.5m)

  27. The Daya Bay Collaboration: China-Russia-US 20 institutions, 89 collaborators X. Guo, N. Wang, R. Wang Beijing Normal University, Beijing 100875, PRC L. Hou, B. Xing, Z. Zhou China Institute of Atomic Energy, Beijing 102413, PRC M.C. Chu, W.K. Ngai Chinese University of Hong Kong, Hong Kong, PRC J. Cao, H. Chen, J. Fu, J. Li, X. Li, Y. Lu, Y. Ma, X. Meng, R. Wang, Y. Wang, Z. Wang, Z. Xing, C. Yang, Z. Yao, J. Zhang, Z. Zhang, H. Zhuang, M. Guan, J. Liu, H. Lu, Y. Sun, Z. Wang, L. Wen, L. Zhan, W. Zhong Institute of High Energy Physics, Beijing 100039, PRC X. Li, Y. Xu, S. Jiang Nankai University, Tianjin 300071, PRC Y. Chen, H. Niu, L. Niu Shenzhen University, Shenzhen 518060, PRC S. Chen, G. Gong, B. Shao, M. Zhong, H. Gong, L. Liang, T. Xue Tsinghua University, Beijing 100084, PRC K.S. Cheng, J.K.C. Leung, C.S.J. Pun, T. Kwok, R.H.M. Tsang, H.H.C. Wong University of Hong Kong, Hong Kong, PRC Z. Li, C. Zhou Zhongshan University, Guangzhou 510275, PRC Yu. Gornushkin, R. Leitner, I. Nemchenok, A. Olchevski Joint Institute of Nuclear Research, Dubna, Russia V.N. Vyrodov Kurchatov Institute, Moscow, Russia B.Y. Hsiung National Taiwan University, Taipei, Taiwan, Republic of China M. Bishai, M. Diwan, D. Jaffe, J. Frank, R.L. Hahn, S. Kettell, L. Littenberg, K. Li, B. Viren, M. Yeh Brookhaven National Laboratory, Upton, NY 11973-5000, USA R.D. McKeown, C. Mauger, C. Jillings California Institute of Technology, Pasadena, CA 91125, USA K. Whisnant, B.L. Young Iowa State University, Ames, Iowa 50011, USA W.R. Edwards, K. Heeger, K.B. Luk University of California and Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA V. Ghazikhanian, H.Z. Huang, S. Trentalange, C. Whitten Jr. University of California, Los Angeles, CA 90095, USA M. Ispiryan, K. Lau, B.W. Mayes, L. Pinsky, G. Xu, L. Lebanowski University of Houston, Houston, Texas 77204, USA J.C. Peng University of Illinois, Urbana-Champaign, Illinois 61801, USA

  28. Accomplishments at Collaboration Meeting • Bylaws were ratified by the Collaboration. • Institutional Board, with one representative from each Member Institution and two spokespersons, was established. • Executive Board was established: Y. Wang (China) A. Olshevski (Russia) C. Yang (China) K.B. Luk (US) M.C. Chu (Hong Kong) R. McKeown (US) Y. Hsiung (Taiwan) • Scientific spokespersons were chosen: Y. Wang (China), K.B. Luk (US) • Project management in China and in the US wereintroduced. • Discussions on the management of the Construction Project. • Task forces were set up. Each task is led by at least one member from China and one from US.

  29. Joint US-China Task Forces International working groups with US-China co-leadership for main detector systems and R&D issues established at February collaboration meeting. • 1. Antineutrino Detector • Co-Chairs: S. Kettell (BNL, USA) • Y. Wang (IHEP, China) • 2. Calibration • Co-Chairs: R.D. McKeown (Caltech, USA) • X. Biao (CIAE, China) • 3. Communications • Co-Chairs: J. Cao (IHEP, China) • K.M. Heeger (LBNL, USA) • W. Ngai (CUHK, Hong Kong) • 4. Liquid Scintillator • Co-Chairs: R.L. Hahn (BNL, USA) • Z. Zhang (IHEP, China) • I. Nemchenok (Dubna, Russia) • 5. Muon Veto • Co-Chairs: L. Littenberg (BNL, USA) • K. Lau (Houston, USA) • Y. Changgen (IHEP, China) • 6. Offline Data Distribution and Processing • Co-Chairs: J. Cao (IHEP) • B. Viren (BNL) • 7. Project Management and Integration • Co-Chairs: B. Edwards (LBNL, USA) • S. Kettell (BNL, USA) • Y. Wang (IHEP, China) • H. Zhuang (IHEP, China) • 8. Simulation • Co-Chairs: J. Cao (IHEP, China) • C. Jillings (Caltech, USA) • 9. Tunneling and Civil Construction • Lead: C. Yang (IHEP, China) • US Consultant: C. Laughton (FNAL, USA)

  30. R&D Plan and Priorities Primary R&D Goals: • Ensure a strong US contribution to the Daya Bay Experiment. • Match the schedule of Chinese R&D and design. • Don’t let US slow project down! • Optimize US scope while minimizing cost. Full R&D funding in FY06 (and FY07): • Enable US input to experiment design. • Timely technology choices. • Early determination of project cost and schedule. • Finalize preparations for CD-1 in about six months. Daya Bay R&D Tasks • Electronics • Muon Veto • Site Development • Project Definition • Simulations • Liquid Scintillator • Antineutrino Detector • Calibration

  31. R&D Task #1 Simulations Primary R&D Goals: • Short-term goal: quantitative guidance for US hardware efforts: • Muon veto and shield for suppression of fast-neutron, gamma-ray and cosmogenic backgrounds: efficiency, tracking accuracy. • Calibration/monitoring to maintain detection efficiency: develop program of source deployments. • Optics: sensitivity of detector response to acrylic thickness, PMT coverage/performance, scintillator transparency, surface reflectivity. • Medium-term goals: • Design of analysis tools: event reconstruction, background identification. • Support for Chinese R&D: • Electronics development (integration time, waveform vs. charge, trigger). Quantitative guidance for US R&D and hardware efforts. Design analysis tools. US Role: • Strong US role in simulations is needed to support US project design. Consequences of reduced R&D funding in FY06: • Possible delay in technology choices and project costing.

  32. R&D Task #2 Gd-Loaded Liquid Scintillator US lead role, based on 3 years of R&D at BNL (ONP + LDRD) • Significant experience synthesizing metal-loaded PC, with high metalconcentrations, 5-10% (w/w) of In, Yb, Nd, for new solar  and  experiments. Primary R&D Goals: • Results readily applied to make dilute ~0.1% Gd in PC for Daya Bay. • However, PC has drawbacks: • Low flashpoint, 48oC • Some health and environmental hazard (N.B. Borexino PC spill at LNGS) • Attacks acrylic plastic (detector vessel walls) • Currently evaluating Gd-LS alternatives to PC. Is Crucial R&D: • Mixture of 20% PC and 80% dodecane • Very promising LS: Linear Alkyl Benzene, LAB, with high 130oC flashpoint, biodegradable (tons available, for industrial detergent production) • Additional R&D support, including postdocs, are needed to exploit these key Gd-LS developments and meet the Daya Bay schedule. Consequences of reduced R&D funding in FY06: • Reduced opportunity for US leadership. • Delays in scintillator choice, in producing LS for prototype, and in cost estimate Require stable (~years) Gd-LS with high light yield, long attenuation length. Explore safer alternatives to pseudocumene, PC.

  33. R&D Task #3 Antineutrino Detector • Measurement of sin2213 <0.01 requires detector systems designed to minimize • systematic uncertainties. • Identical detector modules: • identical scintillator volumes, optical transparency. • facilitate calibration/monitoring system. • Moveable detectors: • design detectors for identical performance at all sites. • engineer support and movement structures. • time critical due to close interface with tunnel/cavern design. Primary R&D Goals: • Mechanical design of central detector. • Design of transportation and installation systems for detectors. • Identify vendors for fabricating acrylic vessels. US Role: • Engineering and leadership experience at LBNL and BNL. Consequences of reduced R&D funding in FY06: • Possible delay or additional risk in civil construction design contract. KamLAND 2005

  34. R&D Task #4 Development of Calibration and Monitoring Tools • Precision measurement of sin2213 <0.01 requires careful studies of detector • systematic uncertainties. • Calibration and monitoring of eight antineutrino detector modules: • need automated monitoring systems to regularlyassess detector stability. • Precise characterization of the detectors: • scintillator masses, attenuation lengths, H/C ratios, and Gd fractions. • Primary R&D Goals: • • Construct prototype calibration system: to be tested with prototype detector module in China. • • Investigate instrumentation and techniques for the precise characterization of detectors and the liquid scintillator target. • US Role — Leadership • US groups have extensive calibration experience in E949, KamLAND and SNO. Consequences of reduced R&D funding in FY06: • Reduced opportunity for US leadership. • Delay in firm cost estimate. KamLAND 2005

  35. R&D Task #5 Front-end and Trigger Electronics • Front-end electronics • Measure charge/waveform of the PMT signal. • Determine the signal arrival times at the PMT’s. • Provide a fast energy sum signal for triggering. • Trigger electronics • Collect inverse beta-decay events with high efficiency. • Collect events to monitor detector and measure backgrounds. Primary R&D Goals: • Refine functionality and specification of front-end electronics. • Develop alternate design concepts for trigger electronics. • Evaluation of prototypes fabricated in China. US Role: • US groups have extensive electronics experience. • Engineering resources at BNL and LBNL. Consequences of reduced R&D funding in FY06: • Compromise US input to a key element of the experiment.

  36. R&D Task #6 Muon Veto/Tracker Understanding muon and spallation backgrounds: • High efficiency, redundant muon vetoes. • Tracking ability for systematic studies and event identification. • Primary R&D Goals: • Evaluate candidate technologies for muon tracker: • Plastic scintillator strips • Resistive Plate Chambers • Liquid scintillator modules • Evaluate candidate technologies for muon veto: • Water pool Cherenkov • Water tank Cherenkov • US Role — Leadership • US groups have extensive scintillator experience. • Consequences of reduced R&D funding in FY06: • Diminished R&D effort will delay technology choice and firm cost estimate. • Reduced opportunity for US leadership.

  37. R&D Task #7 Site Development • Analyze core samples: input for detailed civil construction design studies. • Define surface building and underground halls (space and infrastructure). • Define liquid scintillator purification and handling (space and infrastructure). • Primary R&D Goals: • Define underground hall specifications in order to proceed to final civil design contract. • Interface between experiment design and hall design. • US Role: • Engineering and physics design experience at LBNL and BNL. • Geology expertise at LBNL. • Consequences of reduced R&D funding in FY06: • Reduced input to civil design specification, possible delay or additional risk for civil construction. KamLAND 2005

  38. R&D Task #8 Project Definition • Develop complete project scope and schedule (joint with China). • Define US and Chinese deliverables (joint with China). • Develop US cost and schedule ranges. • Build US project team and organization. • Primary R&D Goals: • Develop the US project scope, cost and schedule. • Coordinate with China on total project scope, cost and schedule. • US Role: • US responsibility. Exploit project experience at LBNL and BNL. • Consequences of reduced R&D funding: • Potentially problematic coordination with Chinese effort. • Delay in development of baseline project. • Less input on overall experiment design. • Risk of delay to Daya Bay experiment. KamLAND 2005

  39. Major US Project Scope Items • Muon Tracker System (Veto Sys) • Gd Loaded Liquid Scint. • Calibration Systems • PMT’s, Base’s & Control • Readout Electronics & DAQ/Trig HW (partial) • Acrylic Vessels (Central Detector) • Detector Integration activities • Project Management activities

  40. US Project Scope & Budget Targets

  41. Beyond Current Scope There are opportunities for the US in other areas also: * These are items in which the US could participate up to ~$1.5M

  42. Overall Project Schedule

  43. Project Development • Schedule/activities over next several months: Determine scale of detector for sizing halls – Continue building strong US team – key people – Conceptual design, scale & technology choices – Firm up US scope, schedule & cost range – Write CDR, prepare for CD-1 – now – June now – summer now – Aug July – Nov Aug – Nov

  44. What does the Daya-Bay Collaboration need? • Support • Schedule Lehman project reviews (fast-track) • CD-1 - ~ November ’06 • CD-2 - ~ September ’07 • Establish International Joint Agency Oversight Group • Decisions • Willing to schedule CD-1 prior to P5 Committee report? • If Daya Bay is the precision reactor experiment – we anticipate accommodating additional collaborators • Funding • R&D funds for FY06 (& 07) • Post-doc supplements to meet schedule • Forward funding of PMT procurement in FY07?

  45. Supplemental Material • Overall project WBS • Preliminary civil construction schedule

  46. Overall Project WBS

  47. Prelim. Civil Construction Sched.

  48. ALT-US Project Scope & Budget Targets

  49. ALT-Beyond Current Scope There are opportunities for the US in other areas also: * These are items in which the US could participate up to ~$3.5M

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