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UHE Neutrino Astronomy

UHE Neutrino Astronomy. Shigeru Yoshida Chiba University http://www-ppl.s.chiba-u.jp/~syoshida/. RESCEU 2003. RESCEU 2003. Outline. UHE n emission – What it can tell Theoretical Bound of n fluxes Extremely High-Energy n generation Cosmic n detection – the current status

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UHE Neutrino Astronomy

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  1. UHE Neutrino Astronomy Shigeru Yoshida Chiba University http://www-ppl.s.chiba-u.jp/~syoshida/ RESCEU 2003

  2. RESCEU 2003 Outline • UHE n emission – What it can tell • Theoretical Bound of n fluxes • Extremely High-Energy ngeneration • Cosmic n detection – the current status • IceCube : reachable to EHE n universe

  3. n / / / / / / / / / / / / / / / / / TeV sources! cosmic rays

  4. Physics motivation • origin and acceleration of cosmic rays •  understand cosmic cataclysms •  find new kind of objects? •  neutrino properties ( , cross sections ..) •  dark matter (neutralino annihilation) • tests of relativitiy .... • search for big bang relics ... • effects of extra dimension etc. ...

  5. Active Galaxies: Jets 20 TeV gamma rays Higher energies obscured by IR light VLA image of Cygnus A

  6. black hole radiation enveloping black hole

  7. You cannot expect too many n! TeV/EGRET observations !! Cosmic Ray observations! Synchrotron cooling p g (p,n) p 2g m n en n You cannot expect too high energies

  8. DUMAND test string NT-200 FREJUS MACRO Theoretical bounds Suppressed by Synchrotron Cooling opaque for neutrons MPR neutrons can escape atmospheric  W&B Mannheim, Protheroe and Rachen (2000) – Waxman, Bahcall (1999)  derived from known limits on extragalactic protons + -ray flux

  9. EHE(Extremely HE) n Synchrotron cooling of m … Production sites with low B Intergalactic space!! • GZK Production • Z-burst • Topological Defects/Super heavy Massive particles

  10. GZK Neutrino Production 0.6 x 10-27 cm2 2.725 K 411 photons / cm3 π ν ＋ ＋ γ μ ＋ ν e p γ p n E = 10 20 eV Conventional Mechanism of EHE neutrinos!! E 0.8 x 10 20 eV ~

  11. GZK n fluxes Yoshida and Teshima 1993 Yoshida, Dai, Jui, Sommers 1997 RESCEU 2003

  12. Orientative order of magnitude [1-3] [3-5] [1-4] [0.2-1] [50-80 Km/s/Mpc] [B≤1nG] [?] [E max >4 1020 eV] Parameters involved in calculation. Predicted fluxes. Parameters γspectral injection index m activity evolution index zmaxz of formation of sources ΩMdensity of matter HoHubble constant Bintergalactic magnetic field ηLρL/ηoρolocal enhancement Emaxmaximum acceleration energy in source (Diego González-Díaz, Ricardo Vázquez, Enrique Zas 2003) RESCEU 2003

  13. (Diego González-Díaz, Ricardo Vázquez, Enrique Zas 2003) CR and νfluxes for different models RESCEU 2003

  14. EHE Constraints by CR/g Deciding factors • Source Evolution • Extension of source distribution • Local source enhancement?

  15. Z-bursts Concept

  16. CRs extending to superEHEs!

  17. Z-burst constraints RESCEU 2003 (Yoshida, Sigl, Lee 1998)

  18. EHE Neutrino Fluxes RESCEU 2003

  19. RESCEU 2003 Cosmic UHE n detection Neutrino Telescopes – Antares, AMANDA, IceCube etc.

  20. Infrequently, a cosmic neutrino is captured in the ice, i.e. the neutrino interacts with an ice nucleus • In the crash a muon (or electron, • or tau) is produced Cherenkov light cone muon interaction Detector • The muon radiates blue light in its wake • Optical sensors capture (and map) the light neutrino

  21. Optical CherenkovNeutrino Telescope Projects ANTARES La-Seyne-sur-Mer, France BAIKAL Russia NEMO Catania, Italy DUMAND Hawaii (cancelled 1995) NESTOR Pylos, Greece AMANDA, South Pole, Antarctica

  22. ANTARES Deployment Sites Thetys Marseille La Seyne sur Mer Toulon Existing Cable Marseille-Corsica Demonstrator Line Nov 1999- Jun 2000 42°59 N, 5°17 E Depth 1200 m New Cable (2001) La Seyne-ANTARES ANTARES 0.1km2 Site 42°50 N, 6°10 E Depth 2400 m ~ 40 deployments and recoveries of test lines for site exploration 0.1 km2 Detector with 900 Optical Modules , deployment 2002- 2004

  23. ANTARES Layout • 12 lines • 25 storeys / line • 3 PMT / storey 14.5 m 350 m Junction box 100 m 40 km to shore ~60-75 m Readout cables

  24. Optical beacon t2 t1 t3 Cylinder Optical fibres Laser Optical Splitter Laser calibration at the CPPM dark room

  25. Optical module 1996-2000 AMANDA II Detector Amundsen-Scott Station South Pole

  26. O(km) long muon tracks Electromagnetic and hadronic cascades  15 m ~ 5 m direction determination by cherenkov light timing Detection of e , ,

  27. The highest energy event (~200 TeV) 300 m

  28. talk HE 2.3-4 cascades (2000 data) Excess of cosmic neutrinos? Not yet ... .. for now use number of hit channels as energy variable ... muon neutrinos (1997 B10-data) accepted by PRL „AGN“ with 10-5 E-2 GeV-1 cm-2 s-1 sr-1 cuts determined by MC – blind analyses !

  29. talk HE 2.3-5 above horizon: mostly atmospheric ‘s below horizon:mostly fake events sky subdivided into 300 bins (~7°x7°) Point source search in AMANDA II Search for excess events in sky bins for up-going tracks PRELIMINARY 697 events observed above horizon 3% non-neutrino background for  > 5° cuts optimized in each declination band no clustering observed - no evidence for extraterrestrial neutrinos ...

  30. DUMAND test string NT-200 FREJUS AMANDA-97 NT-200+ AMANDA-II IceCube AMANDA-00 MACRO Theoretical bounds and future opaque for neutrons MPR neutrons can escape atmospheric  W&B Mannheim, Protheroe and Rachen (2000) – Waxman, Bahcall (1999)  derived from known limits on extragalactic protons + -ray flux

  31. IceTop AMANDA South Pole Skiway 1400 m 2400 m IceCube Talks/Poster by H. Miyamoto this evening • 80 Strings • 4800 PMT • Instrumented volume: 1 km3 (1 Gt) • IceCube is designed to detect neutrinos of all flavors at energies from 107 eV (SN) to 1020 eV

  32. IceCube (1km3 underground observatory) • Sensitive to 10-2 ~ 10-3 of the WB bound • EHE( ~EeV) n -- Almost reachable! GZK, Z-burst, TD... New Physics? Secondary m/t detection

  33. How EHE events look like Eµ=10 TeV ≈ 90 hits Eµ=6 PeV ≈ 1000 hits The typical light cylinder generated by a muon of 100 GeV is 20 m, 1PeV 400 m, 1EeV it is about 600 to 700 m.

  34. EHE (EeV or even higher) Neutrino Events Arriving Extremely Horizontally • Needs Detailed Estimation • Limited Solid Angle Window (srNA)-1 ~ 600 (s/10-32cm2) -1(r/2.6g cm-3) -1 [km] Involving the interactions generating electromagnetic/hadron cascades mN mX e+e- RESCEU 2003

  35. Products ne nm nt m t p e/g ne Weak Weak nm Weak Weak nt Weak Weak Incoming e/g Cascades Decay Weak Pair/decay Bremss Decay m Pair Pair PhotoNucl. DecayPair Decay Pair Bremss Decay Decay Decay Decay Weak t Pair PhotoNucl. p Cascades

  36. Suppression By t decay Muon(Neutrinos) from nm nt Tau(Neutrinos) from nm nt Nadir Angle RESCEU 2003

  37. Atmospheric muon! – a major backgrond But so steep spectrum Upward-going Downward going!! RESCEU 2003

  38. ± π + + e e － － e e ν EHE events! Downward lepton １．４ｋｍ γ γ １ｋｍ Ice γ ν lepton １ｋｍ Rock ν Upward

  39. 11000m 2800 m 1400 m Down-going events dominate… Atmospheric m is attenuated faster… Up Down RESCEU 2003

  40. Flux as a function of energy deposit in km3 • dE/dX~bE DE~DXbE

  41. Flux as a function of energy deposit in km3 • dE/dX~bE DE~DXbE

  42. Intensity of EHE m and t [cm-2 sec-1] RESCEU 2003

  43. IceCube EHE n Sensitivity 90% C.L. for 10 year observation

  44. RESCEU 2003 Summary • UHE n fluxes are constrained by g/CR fluxes. A detection beyond this limit would imply a new class of astronomical objects. • EHE n fluxes are constrained by EGRET g/UHECR fluxes and by the synchrotron cooling of m’s. The loophole to this bound would be the GZK cosmogenic neutrinos with intensity of 10-7~10-8 GeV /cm2 sec sr.

  45. RESCEU 2003 Summary (Cont’d) • AMANDA observatory is getting to reach to its sensitivity to the WB bound. The other telescopes in northern hemisphere would reaches the similar sensitivity. • IceCube observatory would be sensitive to 10-2 of the WB bound. The EHE sensitivity is comparable to the GZK neutrinos fluxes: 3x10-8 GeV /cm2 sec sr in 10 years observation.

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