1 / 43

Neutrino Oscillation

Neutrino Oscillation. Hitoshi Murayama (Berkeley) PRC-US Meeting @ IHEP June 12, 2006. Outline. Past: Why Neutrinos? Present: Era of Revolution Future Conclusion. Past. Why Neutrinos?. Interest in Neutrino Mass. So much activity on neutrino mass already. Why am I interested in this?

erma
Download Presentation

Neutrino Oscillation

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Neutrino Oscillation Hitoshi Murayama (Berkeley) PRC-US Meeting @ IHEP June 12, 2006

  2. Outline • Past: Why Neutrinos? • Present: Era of Revolution • Future • Conclusion Murayama, IHEP, June 12, 2006

  3. Past Why Neutrinos?

  4. Interest in Neutrino Mass • So much activity on neutrino mass already. Why am I interested in this? Window to (way) high energy scales beyond the Standard Model! • Two ways: • Go to high energies • Study rare, tiny effects  Murayama, IHEP, June 12, 2006

  5. Rare Effects from High-Energies • Effects of physics beyond the SM as effective operators • Can be classified systematically (Weinberg) Murayama, IHEP, June 12, 2006

  6. Unique Role of Neutrino Mass • Lowest order effect of physics at short distances • Tiny effect (mn/En)2~(0.1eV/GeV)2=10–20! • Interferometry (i.e., Michaelson-Morley) • Need coherent source • Need interference (i.e., large mixing angles) • Need long baseline Nature was kind to provide all of them! • “neutrino interferometry” (a.k.a. neutrino oscillation) a unique tool to study physics at very high scales Murayama, IHEP, June 12, 2006

  7. Ubiquitous Neutrinos They must have played some important role in the universe! Murayama, IHEP, June 12, 2006

  8. Present Era of Revolution

  9. The Data Evidence for oscillation: • “Indisputable” • Atmospheric • Solar • Reactor • “strong” • Accelerator (K2K) And we shouldn’t forget: • “unconfirmed” • Accelerator (LSND) Murayama, IHEP, June 12, 2006

  10. 2/dof=839.7/755 (18%) m2=2.510-3 eV2 sin22=1 SuperKamiokande Atmospheric  disappear Downwards ’s don’t disappear 1/2 of upwards ’s do disappear Murayama, IHEP, June 12, 2006

  11. SNOSolar  transform in flavor 2/3 of e’s  Murayama, IHEP, June 12, 2006

  12. KamLANDReactor neutrinos do oscillate! Proper time  L0=180 km Murayama, IHEP, June 12, 2006

  13. What we learned • Lepton Flavor is not conserved • Neutrinos have tiny mass, not very hierarchical • Neutrinos mix a lot the first evidence for demise of the Minimal Standard Model Very different from quarks Murayama, IHEP, June 12, 2006

  14. Typical Theorists’ View ca. 1990 • Solar neutrino solution must be small angle MSW solution because it’s cute • Natural scale for Dm223 ~ 10–100 eV2 because it is cosmologically interesting • Angle q23 must be q23 ~ Vcb =0.04 • Atmospheric neutrino anomaly must go away because it needs a large angle Wrong! Wrong! Wrong! Wrong! Murayama, IHEP, June 12, 2006

  15. The Big Questions • What is the origin of neutrino mass? • Did neutrinos play a role in our existence? • Did neutrinos play a role in forming galaxies? • Did neutrinos play a role in birth of the universe? • Are neutrinos telling us something about unification of matter and/or forces? • Will neutrinos give us more surprises? Big questions  tough questions to answer Murayama, IHEP, June 12, 2006

  16. Immediate Questions • Dirac or Majorana? • Absolute mass scale? • How small is q13? • CP Violation? • Mass hierarchy? • Is q23 maximal? • LSND? Sterile neutrino(s)? CPT violation? Murayama, IHEP, June 12, 2006

  17. Future

  18. Immediate Questions • Dirac or Majorana? • Absolute mass scale? • How small is q13? • CP Violation? • Mass hierarchy? • Is q23 maximal? • LSND? Sterile neutrino(s)? CPT violation? Murayama, IHEP, June 12, 2006

  19. Immediate Questions • Dirac or Majorana? • Absolute mass scale? • How small is q13? • CP Violation? • Mass hierarchy? • Is q23 maximal? • LSND? Sterile neutrino(s)? CPT violation? Murayama, IHEP, June 12, 2006

  20. Sterile neutrino (3+1) barely consistent with short-baseline data Sterile neutrinos are strongly constrained by WMAP+SDSS: m<0.26 eV (95%CL)(Seljak, Slosar, McDonald) CPT violation without sterile neutrino excluded by SNO+KamLAND LSND doesn’t fit into the picture WMAP3yr+SDSS HM, Pierce Murayama, IHEP, June 12, 2006

  21. The hell breaks loose • Mini-BooNE will open the box this summer • If Mini-BooNE confirms LSND, it is hard to understand what is going on, because there is currently no simple way to accommodate LSND result with other neutrino data • Multiple sterile neutrinos? 3+2? • Sterile neutrino and CPT violation? • Mass varying neutrinos? • Something even more wild and wacky? Murayama, IHEP, June 12, 2006

  22. What it would take • We will need neutrino “oscillation” experiments with multiple baselines, multiple modes • E~10 GeV, L~10km, looking for  appearance • Redo CDHSW ( disappearance experiment with L=130 & 885m, E=19.2GeV) • E~1 GeV, L~1 km, looking for oscillatory behavior and CP violation in e, or better, e • Some in the air, some in the earth • Probably more • Muon source would help greatly Murayama, IHEP, June 12, 2006

  23. Immediate Questions • Dirac or Majorana? • Absolute mass scale? • How small is q13? • CP Violation? • Mass hierarchy? • Is q23 maximal? • LSND? Sterile neutrino(s)? CPT violation? Murayama, IHEP, June 12, 2006

  24. T2K (Tokai to Kamioka) Murayama, IHEP, June 12, 2006

  25. Immediate Questions • Dirac or Majorana? • Absolute mass scale? • How small is q13? • CP Violation? • Mass hierarchy? • Is q23 maximal? • LSND? Sterile neutrino(s)? CPT violation? Murayama, IHEP, June 12, 2006

  26. LMA confirmed by KamLAND • Dream case for neutrino oscillation physics! • Dm2solar within reach of long-baseline expts • Even CP violation may be probable • Possible only if: • Dm122, s12 large enough (LMA) • q13 large enough Murayama, IHEP, June 12, 2006

  27. q13 decides the future • The value of q13 crucial for the future of neutrino oscillation physics • Determines the required facility/parameters/baseline/energy • sin22q13>0.01conventional neutrino beam • sin22q13<0.01 storage ring,  beam • Two paths to determine q13 • Long-baseline accelerator: T2K, NOA • Reactor neutrino experiment: 2CHOOZ, Daya Bay Murayama, IHEP, June 12, 2006

  28. 32-plane block Admirer NOAFermilab to Minnesota 25kt NOnA MINOS L=810km Murayama, IHEP, June 12, 2006

  29. Far site 1600 m from Ling Ao 2000 m from Daya Overburden: 350 m 910 m Mid site ~1000 m from Daya Overburden: 208 m 570 m 730 m 230 m 290 m Daya Bay Near 360 m from Daya Bay Overburden: 97 m Daya Bay Empty detectors: moved to underground halls through access tunnel. Filled detectors: swapped between underground halls via horizontal tunnels. Ling Ao Near 500 m from Ling Ao Overburden: 98 m Ling Ao-ll NPP (under const.) Ling Ao NPP Entrance portal Daya Bay NPP Total tunnel length: ~2700 m Murayama, IHEP, June 12, 2006

  30. 3 sensitivity on sin2 213 Murayama, IHEP, June 12, 2006

  31. T2K vs NOA • LBL e appearance • Combination of • sin2213 • Matter effect • CP phase  95%CL resolutionof mass hierarchy Murayama, IHEP, June 12, 2006

  32. Accelerator vs Reactor Reactor w 100t (3 yrs) +T2K T2K (5yr,n-only) Reactor w 10t (3 yrs) +T2K 90% CL 90% CL Reactor experiments can help in Resolving the23 degeneracy (Example: sin2223 = 0.95 ± 0.01) Reactor w 100t (3 yrs) + Nova Nova only (3yr + 3yr) Reactor w 10t (3yrs) + Nova 90% CL McConnel & Shaevitz, hep-ex/0409028 Murayama, IHEP, June 12, 2006

  33. My prejudice 13 12 23 • Let’s not write a complicated theory • The only natural measure for mixing angles is the group-theoretical invariant Haar measure • Kolmogorov–Smirnov test: 64% • sin2 2q13>0.04 (2s) • sin2 2q13>0.01 (99%CL) Murayama, IHEP, June 12, 2006

  34. Immediate Questions • Dirac or Majorana? • Absolute mass scale? • How small is q13? • CP Violation? • Mass hierarchy? • Is q23 maximal? • LSND? Sterile neutrino(s)? CPT violation? Murayama, IHEP, June 12, 2006

  35. What about the Big Questions? • What is the origin of neutrino mass? • Did neutrinos play a role in our existence? • Did neutrinos play a role in forming galaxies? • Did neutrinos play a role in birth of the universe? • Are neutrinos telling us something about unification of matter and/or forces? • Will neutrinos give us more surprises? Big questions  tough questions to answer Murayama, IHEP, June 12, 2006

  36. Seesaw Mechanism • Why is neutrino mass so small? • Need right-handed neutrinos to generate neutrino mass , but nR SM neutral To obtain m3~(Dm2atm)1/2, mD~mt, M3~1014–1014GeV Murayama, IHEP, June 12, 2006

  37. Leptogenesis • You generate Lepton Asymmetry first. (Fukugita, Yanagida) • Generate L from the direct CP violation in right-handed neutrino decay • L gets converted to B via EW anomaly  More matter than anti-matter  We have survived “The Great Annihilation” • Despite detailed information on neutrino masses, it still works (e.g., Bari, Buchmüller, Plümacher)

  38. Maybe an even bigger role: inflation Need a spinless field that slowly rolls down the potential oscillates around it minimum decays to produce a thermal bath The superpartner of right-handed neutrino fits the bill When it decays, it produces the lepton asymmetry at the same time (HM, Suzuki, Yanagida, Yokoyama) Decay products: supersymmetry and hence dark matter Neutrino is mother of the Universe? ~ R Origin of Universe amplitude size of the universe Murayama, IHEP, June 12, 2006

  39. LHC finds SUSY ILC measures masses precisely If both gaugino and sfermion masses unify, there can’t be new particles < 1014GeVexcept for gauge-singlets LHC/ILC may help Murayama, IHEP, June 12, 2006

  40. 0 found LHC discovers SUSY ILC shows unification of gaugino and scalar masses Dark matter concordance between collider, cosmology, direct detection CP in -oscillation found Lepton flavor violation limits (e, e conversion,  etc) improve Tevatron and EDM (e and n) exclude Electroweak Baryogenesis CMB B-mode polarization gives tensor mode r=0.16 Plausible scenario If this happens, we will be led to believe seesaw+leptogenesis (Buckley, HM) Murayama, IHEP, June 12, 2006

  41. Conclusions • Neutrino oscillation a unique tool to probe (very) high-energy world • Era of revolution • sin2 213 decides the future • My prejudice: 13 is “large” • Reactor & accelerator LBL expts complementary • To understand “big questions” we need a diverse set of experiments Murayama, IHEP, June 12, 2006

  42. The Ivisibles Murayama, IHEP, June 12, 2006

  43. Murayama, IHEP, June 12, 2006

More Related