Neutrino Oscillations and Astroparticle Physics (1)

1. Neutrino Oscillations and Astroparticle Physics (1) John Carr Centre de Physique des Particules de Marseille (IN2P3/CNRS) Pisa, 6 May 2002 Introduction to Astroparticle Physics Neutrinos - Number - Dirac and Majorana Neutrinos - Mass Measurements - Double Beta Decay - Mixing  Neutrino Oscillations  Cosmology  Dark Matter  High Energy Astronomy

2. Particle Physics Astronomy Astrophysics and cosmology PARTICLE ASTROPHYSICS What is Astroparticle physics ? Particle Astrophysics/Nuclear Astrophysics Use input from Particle Physics to explain universe: Big Bang, Dark Matter, …. Use techniques from Particle Physics to advance Astronomy Use particles from outer space to advance particle physics

3. Story of the Universe

4. Make-up of Universe

5. Dark Matter Evidence: Need to hold together Galaxy Clusters Explain Galaxy Rotation velocities Astronomy object candidates : Brown Dwarfs (stars mass <0.1 Msun no fusion) - some but not enough White Dwarfs ( final states of small stars) - some but not enough Neutron Stars/Black Holes ( final states of big stars.) - expected to be rarer than white dwarfs Gas clouds - 75% visible matter in the universe, but observable Particle Physics candidates: Neutrinos - Evidence for mass from oscillation, not enough for all Axions - Difficult to detect …. Neutralinos - Particle Physicist Favourite !

6. Cosmic Rays Primary: p 80 %,  9 %, n 8 % e 2 %, heavy nuclei 1 %  0.1 %,  0.1 % ? charged particles protons ions electrons neutral particles photons neutrinos Primary cosmic rays produce showers in high atmosphere at ground level :~ 1/sec/m² Secondary at ground level:  68 %  30 % p, n, ... 2 % 100 years after discovery by Hess origin still uncertain

7. Particle Acceleration E  BR Large Hadron Collider R  10km, B  10T  E  10 TeV Tycho SuperNova Remnant R  1015km, B  1010T  E  1000 TeV ( NB. E  Z  Pb/Fe higher energy)

8. Particle Physics  Particle Astrophysics LHC CERN, Geneva, 2005 Saturne, Saclay, 1964 Terrestrial Accelerators Cosmic Accelerators Active Galactic Nuclei Binary Systems SuperNova Remnant Diameter of collider Cyclotron Berkeley 1937 Energy of particules accelerated

9. FNAL LHC FNAL LHC Ultra High Energy from Cosmic Rays From laboratory accelerators From cosmic accelerators Particle cross-sections measured in accelerator experiments Flux of cosmic ray particles arriving on Earth particle flux /m2/st/sec/GeV cross-section (mb) Fixed target beamlines Colliders Colliders 1 102 104 106 108 1010 1012 Energy GeV 1 102 104 106 108 1010 1012 Energy GeV Ultra High Energy Particles arrive from space for free: make use of them

10. Multi-Messanger Astronomy Photons absorbed on dust and radiation Neutrinos direct Protons deviated by magnetic fields absorption cut-off mean free path -rays:  + 2.7k >1014eV 10 Mpc proton: p + 2.7k 0 + X >5.1019eV 50 Mpc nuclei: photo-disintegration >5.1019eV 50 Mpc neutrinos:  + 1.95K  Z+X >4.1022eV (40 Gpc) magnetic deflection (rad)= L(kpc) Z B(G)/E(EeV) Galaxy B=2G, Z=1, L=1kpc -> =12deg at 1019eV

11. Neutrino Mass in the Universe

12. Neutrino History 1931 - Predicted by Pauli 1934 - Fermi develops a theory of radioactive decays and invents name neutrino 1959 - Discovery of neutrino (e) is announced by Cowan and Reines 1962 - Experiments at Brookhaven and CERN discover the second neutrino:  1968 - First evidence that solar neutrino rate half expectation: "solar neutrino problem” 1978 - Tau particle is discovered at SLAC by Perl et al.: infer third neutrino 1985 - First reports of a non-zero neutrino mass (still not confirmed) 1987 - Kamiokande and IMB detect bursts of neutrinos from Supernova 1987A 1988 - Kamiokande reports only 60% of the expected number of atmospheric  1989 - Experiments at LEP determine three neutrinos from Z line width 1997 - Super-Kamiokande see clear deficits of atmospheric  and solar e 1998 - The Super-Kamiokande announces evidence of non-zero neutrino mass 2000 - DONUT experiment claims first observation of tau neutrinos

13. First observation of Neutrino Reines and Cowan 1959: Target made of 400 l water and cadmium chloride near reactor. The anti-neutrino coming from the nuclear reactor interacts with a proton of the target matter, giving a positron and a neutron. The positron annihilates with an electron of the surrounding material, giving two simultaneous photons and the neutron slows down until it is eventually captured by a cadmium nucleus, implying the emission of photons some 15 microseconds after those of the positron annihilation. All those photons are detected and the 15 microseconds identify the neutrino interaction.

14. 106 t 104 b c  102  d u 1 e  102 104 e 106 Three Generations of Particles Mass (Mev/c2)  s At present only limits of absolute masses of neutrinos Oscillations give neutrino mass differences

15. Discovery of  (?) DONUT experiment, FNAL

16. Discovery of (?) 4  events identified

17. Number of Neutrino Families From Big Bang Nucleosynthesis Data

18. Number of Neutrino Families From Big Bang Nucleosynthesis Fraction 4He Dependence on Neutron lifetime Lifetime (s) Reference 918 ± 14 [Chr72] 903 ± 13 [Kos86] 891 ± 9 [Spi88] 876 ± 21 [Las88] 877 ± 10 [Pau89] 888 ± 3 [Mam93] 878 ± 30 [Kos89] 894 ± 5 [Byr90] 888.4 ± 4.2 [Nes92] 882.6 ± 2.7 [Mam89] 887.0 ± 2.0 [PDG94] Fraction Li

19. Number of Neutrino Families Measurements from LEP of width of Z resonance N = 2.994±0.012

20. XY  M()=0 M()0 events energy Neutrino Mass Measurements Direct mass measurements - Time-of-flight measurements from distant objects - Kinematics of Weak Decays Indirect searches ( effects which only exist if M()  0 ) - Neutrino Oscillations - Neutrinoless Double Beta Decay

21. Dirac and Majorana Neutrinos ( See Akhmedov ‘ Neutrino physics ’ : hep-ph/0001264 ) For massive fermion, mass term in Lagrangian: Mass term couples left and right-handed components: Dirac Neutrino: left and right-handed fields completely independent Majorana Neutrino : left and right-handed fields charge conjugates then: so: : Majorana field is self charge-conjugate Majorana neutrino is its own anti-particle

22. Dirac and Majorana masses Mass matrices : Dirac mD, Majorana mL, mR n species of neutrino: n  n complex matrices General neutrino mass term in Lagrangian: where:

23. Neutrino Mass from Time-of-flight Supernova 1987a in Large Magellenic Cloud L = 50 kpc (150 light years ) p + e n + ne e+ + e ne + ne, , nm +nm energy (MeV) t = 0 unknown use arrival time as function of energy events  time (sec) time (sec) M(e ) < 23 eV/c2

24. Limits on M( ) Measured in  decays at LEP e+e  +    n  (n=3, 5, 6) contours are limits when E = 0

25. Limits on M( ) In tau rest frame energy of hadronic system h: m2 + mh2  m2 E*h = 2 m Total decays 2939 :   2  +  52 :   3  2+ 3 :   3  2+ 0  only events with high mh contribute to M( ) limit M( ) < 18.2 MeV/c2 (95% CL)

26. Limits on M( ) M( ) < 170 keV/c2 (95% CL)

27. Limits on M(e ) Detailed study of end-point of spectrum: many experiments

28. Limits on M(e ) Mainz spectrometer

29. Limits on M(e ) End-point spectra Troitsk experiment Mainz experiment

30. Limits on M(e )

31. Only possible M()  0 Majorana neutrino    Double Beta Decay A(Z,N)  A(Z+2, N2)+2e A(Z,N)  A(Z+2, N2)+2e+2e 2 0 (neutrino-less)

32. Only a few possible double beta isotopes Must be energetically allowed and single beta decay suppressed

33. Example: 100Mo in MOON detector Mo(42,48)  Ru(44, 46) Both: Double beta decay: 100Mo  100 Ru + 2 e (+ 2 e ) Solar neutrino: 100Mo + e 100Mo  100 Tc + e 100 Ru + e

34. Physics beyond Standard Model in 0 Right-Handed Currents Majoron production Supersymmetry

35. NEMO 3 (100Mo) At Modane laboratory in Frejus tunnel

36. Heidelberg-Moscow (76Ge) At Gran Sasso laboratory expected 0 signal of 2 Half-life T½2 = 1.55±0.17  1021 years T½0 > 3.1  1025 years (90% CL)

37. Summary of Double Beta Decay Results Limits on Majorana neutrino mass

38. Latest News August 2001 limit: T½0 > 3.1  1025 years (90% CL) M < 0.3 eV /c2 January 2002 evidence: T½0 = (0.8-18.3)  1025 years (95%CL) 1.5  1025 years: best value M = 0.11-0.56 eV /c2 (95% CL) = 0.39 eV /c2: best value - same data, not all same people…..

39. Summary of Particle Data Group 2001 Number of light : 2.994  0.012 M(e ) < 3 eV /c2 M( ) < 190 keV/c2 M( ) < 18.2 MeV/c2 Majorana mass M(e ) < 0.24 eV /c2 ( dependent on Nuclear Matrix Element)

40. Possible Neutrino Mass Splitting M(e) < 3 eV ? 0 Zero of mass scale ?

41. Ue1 Ue2 Ue3 U1U2U3 U1 U2 U3 e   1 2 3 Vud Vus Vub Vcd Vcs Vcb Vtd Vts Vtb d s b d s b = = Neutrino Mixing Analogy with quarks For massive particles: flavour eigenstates can be different from mass eigenstates leptons quarks U : leptonic mixing matrix V : quark mixing matrix, ( CKM matrix ) Standard Model, U and V unitary 3  3 complex matrices:  Uk* Uk= 

42. W decays leptons quarks W  q q W  l l W  e 1   Ue1 2  e2   Ue2 2  e2   Ue3 2   1   U1 2  2   U2 2  3   U3 2   1   U1 2  2   U2 2  3   U3 2 W  u d   Vud 2  u s  Vus 2  u b   Vub 2  c d   Vcd 2  c s  Vcs 2  c b   Vcb 2 (  t X m(t) > m(W) ) Unitarity:  Ue1 2 + Ue2 2 +  Ue3 2 = 1 etc.  Vud 2 + Vus 2 + Vub 2 = 1

43. 0.970.220.003 0.22 1.0 0.04 0.006 0.04 1.0 Numerical Values Vud Vus Vub Vcd VcsVcb Vtd Vts Vtb Ue1 Ue2 Ue3 U1U2U3 U1 U2 U3 ?

44. Ue1 Ue2 Ue3 U1U2U3 U1 U2 U3 0.970.220.003 0.22 1.0 0.04 0.006 0.04 1.0 10 0 0 1 0 0 0 1 Possibilities for Leptonic Mixing 1/21/2 0 1/2 1/2 1/2 1/2 1/2 1/2 No mixing like quarks bi-maximal mixing If Ue3 = 0 no CP violation ( like Vub = 0 for quarks)

45. Ue1 Ue2 Ue3 U1U2U3 U1 U2 U3 CP Violation in Neutrino Sector If Ue3 = 0 no CP violation ( like Vub = 0 for quarks) Same parameterisation as quark sector: CP conservation: