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Solar Fusion Prozesses

Solar Fusion Prozesses. H. Bethe. W. Fowler. pp - 1. pp -2. pp -3. Solare n Spektrum und Experimente. Homestake. Kamiokande, SK. SNO. Gallex, Sage. The Homestake Experiment. Das Pionierexperiment: Homestake. Neutrino Detektion 37 Cl + n e 37 Ar + e threshold energy 814 keV

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Solar Fusion Prozesses

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  1. Solar Fusion Prozesses H. Bethe W. Fowler pp - 1 pp -2 pp -3

  2. Solare n Spektrum und Experimente Homestake Kamiokande, SK SNO Gallex, Sage

  3. The Homestake Experiment Das Pionierexperiment: Homestake Neutrino Detektion 37Cl + ne37Ar + e threshold energy 814 keV target 615 t Perchlorethylen exposition to solar neutrinos ~ 60 days extraction of Ar - atoms Detection of Ar decay (T1/2 = 35 days) Ray Davis, 1966 Noble price 2002

  4. Ergebnis Homestake Chlor Experiment Empfindlich auf 7-Be und hauptsächlich auf 8-B Neutrinos Resultat: 2.56 +_ 0.23 SNU Sonnenmodell: 7.6 + 1.3 - 1.1 SNU Beginn des „Solaren Neutrino Problems“ ! Dakota (USA)

  5. SuperKamiokande • dimensions: • 41.4 m (hight) • 39.3 m (diameter) • water Cherenkov Detector (~ 50 kton high purity water) • solar-n detection by neutrino – electron scattering • Energy threshold ~ 5 MeV (sensitiv to 8B - n)

  6. Auch SuperK detects only 45 % of expected events (this is only a bit more than Homestake (Davis)) Ratenvariation übers Jahr Energie Spektrum Keine Abweichung von der erwarteten Form des ß-Spektrums

  7. Gallex & GNO Integral detection of solar all solar neutrinos ! 71Ga + ne -> 71Ge + e ~5 decays per extraction

  8. Situation nach GALLEX (~ 20 Jahre nach Homestake) Hinweis auf nicht standard Eigenschaften der Neutrinos Theoretische Vorhersagen

  9. This was the first evidence for non standard neutrino properties(neutrino decay, oscillation..? )

  10. Hypothesis: Neutrino Oscillation ((B. Pontecorvo) Condition 1) Eigenvalues of weak interaction # mass eigenvalues 2) Neutrinos are massive ν(e) = ν(1)cos (θ) + ν(2) sin(θ) ν(μ) = ν(1)-sin (θ) + ν(2) cos(θ) Time development |νe(t) > = |ν1(0) > exp (-iE1 t ) + |ν2 (0) > exp (–i E2 t) with Ei ²= m1² + p1² und Δ² = m²2 – m²1 P ν(e) = 1- sin² 2θ sin² (1,27Δ²/E²(ν))

  11. SNO: Sudbury Neutrino Observatory • geladene Stromwechselwirkung (cc) ne + D -> p + p + e • neutrale Stromwechselwirkung (nc) nx+ D ->nx + p + n • Elektronstreuung (cc + nc) nx + e ->nx + e • nc-events ~ 30 / d • es-events ~3 / d • cc-events ~ 30 / d (SSM)

  12. Energie- spektrum Richtungsverteilung Räumliche Verteilung im Detektor

  13. Sonnen-n ändern ihren Flavour!(sie verwandeln sich auf dem Weg zur Erde vom e-Typ in den m, oder t-Typ) Insgesamt kommen genau so viele Neutrinos an wie vorausgesagt!

  14. Neutrino Flavour Transition prooved

  15. verzögertes event: 180μsec promptes event: Ev – 0.77 MeV (n Spektroskopie) Detektion von Reaktorneutrinos Ev > 1.8 MeV

  16. Search for neutrino oszillations, solar neutrino astronomy at low energies Phys. Rev. Lett. 90 (2003) 021802 Experiment at ILL Gösgen Borexino Bugey ? ? Gallium Solar neutrinos 1.5 x 1011

  17. Oscillation of Neutrinos from the Atmosphere Superkamiokande

  18. Survival probability: 0 3 2 1 L in Losz Neutrino Oscillations

  19. L ≈ 20 km atmosphericneutrinos:Ev ~ GeV L ≈ 13000 km Oscillations and Atmospheric Neutrinos Pion production and subsequent decays (incl. muon)

  20. Atmospheric Neutrinos and SuperKamiokande 50 kt Water Cherenkov Detector Charged current reactions nm + N ->m + N` and ne + N -> e + N`

  21. SuperKamiokande (Japan) • ein Detektor mit ca. 50 kton Reinstwasser • atmosphärische und solare Neutrinos • atm.: CC Wechselwirkung

  22. Particle ID and the number of Cherenkov rings ne + N  e + N’ + (X) Category 1: fully contained events, 1 ring Here: Electron like event ne + N  e+ N’ + (X)

  23. nm+ N m + N’ + (X) Category 1: fully contained events, 1 ring Here: Muon like event

  24. nm + N  m+ N’ + p + (X) Fully contained events, multiple rings Here: Muon event

  25. Multi-ring event

  26. Muon 480 MeV

  27. Electron 0.7 GeV

  28. Muon 1 GeV

  29. Through going muon

  30. zenith angle distributions null oscillation best fit with oscillation data

  31. Muon events Electron events νμ νe m e No-oscillation Oscillation Up going Up going Neutrinos

  32. Result atmospheric Neutrino-Oscillations • Confirmed by • MACRO (Gran Sasso) • Soudan (USA) • K2K accelerator long baseline (250 km) experiment • MINOS (USA) acc. exp. in 2006 Best fit:m2atm = 2.5×10-3 eV2 sin22θatm = 1.0

  33. What do we know today about neutrino oscillation • ne<-> nm , ntsolar neutrinos • non maximal mixingund • Dm2 ~ 10-4 eV2 • nm<-> ntatmospheric neutrinos • large mixing ( close to maximal) • Dm2~ 2.5 x 10-3 eV2 • ne

  34. Parametrization of Neutrinomixing • Neutrino-mixing matrix: • 3 mixing angles: θ12, θ23, θ13 • 1 CP-violating Dirac-Phase: δ θsol θ13, δ θatm • In addition, if Majorana neutrinos: • 2 CP-violating Majorana-phases

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