Experimental Neutrino Physics: Upgrades & Perspectives

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1 Experimental Neutrino Physics: Upgrades & Perspectives Ernesto Kemp for the neutrino group University of Campinas UNICAMP Gleb Wataghin Physics Institute IFGW Cosmic Rays and Chronology Department DRCC

2 Outline Physics Challenges Experiments The context of neutrino experiments in the frontier of Physics Brazilians researchers/institutions within this scenario Perspectives and Future Opportunities Current collaborations: upgrades Perspectives for future activities Conclusion 2

3 Physics Challenges 3

4 Physics Challenges 4

5 Physics Challenges The Intensity Frontier Measurements of the mass and other properties of neutrinos are fundamental to understanding physics beyond the Standard Model and have profound consequences for the understanding of the evolution of the universe. (PG. 3) Recent striking discoveries make the study of the properties of neutrinos a vitally important area of research. Measurements of the properties of neutrinos are fundamental to understanding physics beyond the Standard Model and have profound consequences for the evolution of the universe. The latest developments in accelerator and detector technology make possible promising new scientific opportunities in neutrino science as well as in experiments to measure rare processes. (PG. 10) The panel recommends a world-class neutrino program as a core component of the US program (PG. 3) 5

6 Physics Challenges 3. 2 The Intensity Frontier : Neutrino Physics and Precision Measurements At the Intensity Frontier, precision measurements of the properties of leptons and quarks can lead the way to resolving some of the universe s deepest mysteries Neutrino physics Neutrino physics has had a long and distinguished history, We outline an ambitious vision that builds on that strong scientific tradition to capture the unique scientific opportunities of neutrino science. Results of recent experiments have revolutionized and brought renewed excitement to this field. They have shown that neutrinos have nonzero masses, mix with one another, and oscillate among the neutrino flavor states. Cosmology tells us that the neutrino masses are very small, less than one millionth of the electron s mass. Oscillation studies find tiny nonzero neutrino mass differences between generations, but large values of two of the three mixing angles, θ23 ~ 45o and θ12 ~ 32o. Currently we only have an upper limit of about 10 o on the third angle, θ13. Collectively, these advances in neutrino physics have opened the first crack in the Standard Model of particle physics. They have significantly changed our view of neutrinos and the special role they play in elementary particle physics, astrophysics and cosmology. In the coming years, neutrino physics presents exciting opportunities: the measurement of the mixing angle between the heaviest and lightest neutrinos, determination of the hierarchy of neutrino masses, the search for matter-antimatter asymmetry (CP violation) in neutrino mixing, and lepton number violation. These opportunities are fundamental to the science of particle physics and have profound consequences for the understanding of the evolution of the universe. 6

Physics Challenges Questions for the future The great progress in neutrino physics over the last few decades raises new questions and provides opportunities for major discoveries.

7 Physics Challenges Questions for the future The great progress in neutrino physics over the last few decades raises new questions and provides opportunities for major discoveries. Among the compelling issues today: 1) What is the value of θ13, the mixing angle between first- and third-generation neutrinos for which, so far, experiments have only established limits? Determining the size of θ 13 has critical importance not only because it is a fundamental parameter, but because its value will determine the tactics to best address many other questions in neutrino physics. 2) Do neutrino oscillations violate CP? If so, how can neutrino CP violation drive a matter-antimatter asymmetry among leptons in the early universe (leptogenesis)? What is the value of the CP violating phase, which is so far completely unknown? Is CP violation among neutrinos related to CP violation in the quark sector? 3) What are the relative masses of the three known neutrinos? Are they normal, analogous to the quark sector, (m 3>m2>m1) or do they have a so-called inverted hierarchy (m 2>m1>m3)? Oscillation studies currently allow either ordering. The ordering has important consequences for interpreting the results of neutrinoless double beta decay experiments and for understanding the origin and pattern of masses in a more fundamental way, restricting possible theoretical models. 4) Is θ23 maximal (45o)? if so, why? Will the pattern of neutrino mixing provide insights regarding unification of the fundamental forces? Will it indicate new symmetries or new selection rules? 5) Are neutrinos their own antiparticles? Do they give rise to lepton number violation, or leptogenesis, in the early universe? Do they have observable laboratory consequences such as the sought-after neutrinoless double beta decay in nuclei? 6) What can we learn from observation of the intense flux of neutrinos from a supernova within our galaxy? Can we observe the neutrino remnants of all supernovae that have occurred since the beginning of time? 7) What can neutrinos reveal about other astrophysical phenomena? Will we find localized cosmic sources of very-highenergy neutrinos? 8) What can neutrinos tell us about new physics beyond the Standard Model, dark energy, extra dimensions? Do sterile neutrinos exist? 7

8 Experiments with Brazilian Scientists Neutrino Properties: oscillations Double Chooz MINOS MINOS+ Neutrino Interactions and Properties: nuclear scattering and oscillations MINERVA Astrophysical Neutrinos LVD Pierre Auger Observatory Neutrino Applied Physics Xenon Neutrinos-ANGRA Especial Remark: ANDES 8

9 Experiments in this proposal Neutrino Properties: oscillations Double Chooz MINOS MINOS+ Neutrino Interactions and Properties: nuclear scattering and oscillations MINERVA Astrophysical Neutrinos LVD Pierre Auger Observatory Neutrino Applied Physics Xenon Neutrinos-ANGRA Special Remark: ANDES 9

10 Future Activities: 5 years scenario Experiments specifically related to studies of neutrino properties I. The Double Chooz Collaboration (DC) operating a pair of functionally identical detectors to measure neutrino mixing properties by the desapearence of electron antineutrinos from nuclear reactors II.Experiments in the ambit of FERMILAB (U.S.A.): MINOS/MINOS+ accelerator-based neutrino beams to explore longest baselines to measure muon neutrinos flavor conversion. Upgrades in existing collaborations Near future perspective The groups envisage to join a common experiment: Long Baseline Neutrino Experiment LBNE Project. 10

11 Experiments: Double Chooz 11

12 Experiments: Double Chooz 12

13 Experiments: Double Chooz Found non-zero value of θ13 Strong requirements to get rid of limitations from Chooz results (sistematics) Identical detector placed in different distances is a solution main sistematics and uncertainties are canceled 13

14 Double Chooz: antinu-e detection 14

15 Double Chooz main backgrounds 15

16 Double Chooz main backgrounds 16

17 Double Chooz main backgrounds 17

18 Double Chooz main backgrounds 18

19 Double Chooz main backgrounds 19

20 Double Chooz: error budget 20

21 Double Chooz Brazilian contribution: Muon Electronics VME 6U Board waveform digitizer + time stamp 30 units produced and tested. Data acquisition with several modules being tested (APC-Paris + UNICAMP) 21

22 Double Chooz: upgrades 22

23 Double Chooz: next main goals 23

24 MINOS: 2 magnetized iron-scintillator tracking calorimeters NIMA (2008) Functionally equivalent Near&Far Magnetized steel planes <B> = 1.3 T cm2 scintillator strips 2.54 cm steel sheets Moliere radius = 3.7 cm Sampling = 1.4 radiation lengths

25 Experiments: MINOS+ MINOS+: A proposal for the continued running of the MINOS detectors in the NOvA era (3 years extension) goals: 1. improve the understanding of the neutrino beam flux (on-axis versus off-axis) 2. measurement of sin2θ and Δm2, with improved precision (by combining data with NOνA) 3. study high-energy neutrinos 4. search for sterile neutrinos 5. search for tau neutrinos (with better kinematic cuts we could isolate tau neutrino events) 6. non-standard interactions 7. muon neutrino time of flight 25

26 Statistical precision in MINOS+ Significant improvement in statistical precision in the 4-10 GeV region Over 3000 CC events per year in that interval A unique high-statistics experiment with chargesign measurement in an previously unexplored region

27 θ 23 and m 2 23 Improvements in m223 can be achieved when combined with Nova & T2K > ~1% measurement 1% measurements of m232 and m231 can aid mass hierarchy determination (e.g. arxiv.org/ ) Some contribution to knowledge of sin22θ23

28 MINOS+ Search for sterile neutrinos via disappearance Oscillation spectrum fair insensitive to primary oscillation parameters in this region Must to incorporate oscillations in the ND for higher mass splittings

29 MINOS+ sterile reach Ue4 2 = sin2θ14 Uµ4 2 = cos2θ24 * sin2θ24 sin2(2θµe) = 4 Ue4 2 * Uµ4 2

30 Non-standard interactions & extra dimensions Dimension 5 non-standard contact interactions show up in the region of study MINOS, L = 735 km (without matter effect) 1.0 P(νµ νµ) 0.8 m0 = Standard (Normal) Standard (Inverted) R = 5x10 m (Normal) -7 R = 5x10 m (Inverted) 0.2 δ= sin 2θ23= =7.56x10 ev sol m atm=2.49x10 ev sin θ12=0.319 m 2 sin 2θ13= Neutrino Energy (GeV) The same ratio could show half micron sized extra dimensions P.A.N.Machado,H.Nunokawa,R.Zukanovich Funchal, hepph/ v1 J. Kopp, P.A.N. Machado and S.Parke, Phys.Rev.D82: (2010). Alexander Friedland, Cecilia Lunardini, Phys. Rev. D74 :033012, 2006.

31 Atmospherics Magnetic field allows identification of μ+ and μ Complementary to SuperK who ID νe events Not conclusive, but combined with SuperK, could give information on mass hierarchy

32 MINOS+ Summary High precision, long baseline, new energy regime MINOS+ will pick up where MINOS leaves off > Large reach in sterile search > Non-standard effects could be seen with MINOS+ High precision standard parameter measurement of m223 may be important in the future > Another way to the mass hierarchy? A unique high-statistics study in an previously unexplored region

33 Future Perspective Double Chooz group + MINOS group LBNE : joint effort 33

34 Long Baseline Neutrino Experiment: LBNE 34

35 Long Baseline Neutrino Experiment: LBNE The LBNE Collaboration 347 members from 62 institutions in the United States, Europe and Asia Studies already done: a complete, practical and achievable configuration for the experiment: Neutrino source Fermilab Far Detector site: Sanford Underground Research Facility (SURF) in the former Homestake gold mine in Lead, South Dakota Development of technical designs: neutrino beam far detector and near detector all of the civil engineering for the facilities at Fermilab and SURF required to support the program 35

36 LBNE motivations Standard Model Remarkably accurate description of the elementary particles/interactions But is incomplete Results from the last decade 3 known types of neutrinos have nonzero mass, mix with one another and oscillate between generations implies physics beyond the Standard Model. Remarkable progress has been made in this decade to understand the new phenomena of neutrino oscillations We have all the ingredients for a scientifically well motivated and comprehensive program of measurements of neutrino oscillations and fundamental symmetries using leptons. a more fundamental underlying theory must exist 36

37 LBNE motivations Remarkable progress has been made in this decade to understand the new phenomena of neutrino oscillations. We have all ingredients for a scientifically well motivated and comprehensive program of measurements of neutrino oscillations and fundamental symmetries using leptons. 37

38 LBNE motivations The Long-Baseline Neutrino Experiment Collaboration (LBNE) : Experiment that will fully characterize neutrino oscillation phenomenology using a high-purity νμ beam, operated in both beam polarities (particle/antiparticle) Main Goals: Measure full oscillation patterns in multiple channels, precisely constraining mixing angles and mass differences. Search for CP violation both by measuring the CKM phase and by explicitly observing differences in νμ / νμ -bar oscillations. Cleanly separate matter effects from CP-violating effects δcp determine the ordering of the three neutrino mass eigenstates 38

39 LBNE key elements the right baseline highly capable detector high statistics measurements efficient measure of complex final states Clean separation of signal/background beam: High power broad-band High-purity sign-selected neutrino beam highly capable near detector precise measurements of flux spectra of all neutrino species in the beam Precise measurements of cross-sections relevant for the oscillation physics 39

40 LBNE: FERMILAB beam and baseline MINOS 700 km 1300 km depth of 1480 m 4300 Sanford Underground Laboratory Lead, South Dakota 40

41 LBNE: beam and baseline The baseline should be long enough to cleanly separate the oscillation asymmetry between νμ / νμ -bar due to the (non-cp-violating) matter effect from that due to true CP violation. Too short baseline => fundamental ambiguities between these two effects. 800 km 1300 km 41

42 LBNE: beam and baseline Too long baseline: asymmetry due to the matter effect can become so large Full suppression the flux of ν (ν -bar) in the case of the μ normal (inverted) mass hierarchy km 2500 km 42

43 LBNE: highly capable Far-Detector Main design elements of the LBNE LAr TPC far detector. Upper left is an isometric cutaway drawing of the LAr TPC in it membrane cryostat, with alternating vertical anode and cathode planes. Lower left is a membrane cryostat in a liquefied natural gas tanker. The pink rectangle indicates roughly the cross-section size of the LBNE cryostat. Upper right is a conceptual design of one anode plane assembly module. Lower right shows the design for the mounting rail system that will support the anode and cathode planes. 43

44 LBNE: highly capable Far-Detector Liquid Argon (LAr) TPC: GEANT4 fiducial mass = 34 kton low-rate, large-volume, high-precision particle physics experiments excellent 3D resolution Event topologies and kinematics: Particle identification: electrons, muons, photons, kaons, pions and protons 44

45 LBNE: high precision Near-Detector Magnetized LAr TPC Near Detector 45

46 Sunfor Underground Research Facility SURF: existing laboratory Yates shaft Administration building Corridor 1480 m depth Clean rooms: Majorana Demonstrator LUX experiment 46

47 LBNE time-line 47

48 Conclusions: Brazilian group of experimental neutrino physics is participating in major experiments in frontier studies of neutrino properties The Brazilian scientific community has an unique opportunity to stay tuned with development of new technologies and their applications even in a broader scope than experimental particle physics. Close contact of Brazilians teams with the current experimental efforts enables a stronger interaction with the phenomenological and theoretical groups in our country deepest and faster feedback in both directions. 48

49 Conclusions: LBNE Significant opportunity for new collaborators (Brazilian group): Collaboration on the design and construction: far detector near detector neutrino beam Interest in the advanced state of LAr-TPC Collaboration on the any aspect of the near detector/beam: Brazil and the U.S. working together to develop and implement the best possible configuration major step in advancing this science The Brazilian group has been invited to participate as full collaborators: Possibility: Cosmic Ray VETO Choice of technology (RPC?) Excellent opportunity to participate in a cutting-edge program of measurements of neutrino oscillations and fundamental symmetries using leptons. 49

50 Grato pela atenção! 50

51 Experiments: MINOS 51

particles they generate The number of muon neutrinos measured in the

52 Experiments: MINOS The detectors are made of steel plates interleaved with scintillators We identify the neutrinos through the trajectory of the particles they generate The number of muon neutrinos measured in the detector is far less than expected based on the near detector if there was no oscillation 52

Experimental Neutrino Physics in Brazil

Experimental Neutrino Physics in Brazil Ernesto Kemp kemp@ifi.unicamp.br University of Campinas UNICAMP Outline 2 Neutrino: a building block The three types of neutrinos in the standard model are the lightest