UHE Neutrino Astronomy Shigeru Yoshida Chiba University RESCEU 2003

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

TeV sources! cosmic rays //////////////////////////////////

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....

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

radiation enveloping black hole

 You cannot expect too many ! p  (p,n)  22 e e  TeV/EGRET observations !! Cosmic Ray observations! Synchrotron cooling You cannot expect too high energies

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

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

GZK Neutrino Production K 411 photons / cm x cm 2 γ p n p π ＋ μ ＋ ν e ＋ ν γ E = eV E 0.8 x eV ~ Conventional Mechanism of EHE neutrinos!!

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

RESCEU 2003 γ spectral injection index m activity evolution index z max z of formation of sources Ω M density of matter H o Hubble constant B intergalactic magnetic field η L ρ L /η o ρ o local enhancement E max maximum acceleration energy in source Parameters Orientative order of magnitude [1-3] [3-5] [1-4] [0.2-1] [50-80 Km/s/Mpc] [B≤1nG] [?] [E max > eV] Parameters involved in calculation. Predicted fluxes. (Diego González-Díaz, Ricardo Vázquez, Enrique Zas 2003)

RESCEU 2003 CR and ν fluxes for different models (Diego González-Díaz, Ricardo Vázquez, Enrique Zas 2003)

EHE Constraints by CR/  Deciding factors Source Evolution Extension of source distribution Local source enhancement?

Z-bursts Concept

CRs extending to superEHEs!

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

EHE Neutrino Fluxes RESCEU 2003

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

neutrino muon Cherenkov light cone Detector interaction 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 The muon radiates blue light in its wake Optical sensors capture (and map) the light

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

Demonstrator Line Nov Jun °59 N, 5°17 E Depth 1200 m ANTARES 0.1km 2 Site 42°50 N, 6°10 E Depth 2400 m Existing Cable Marseille-Corsica Marseille Toulon La Seyne sur Mer New Cable (2001) La Seyne-ANTARES ANTARES Deployment Sites ~ 40 deployments and recoveries of test lines for site exploration 0.1 km 2 Detector with 900 Optical Modules, deployment Thetys

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

Laser calibration at the CPPM dark room Optical fibres t1t1 t2t2 t3t3 Optical Splitter Laser Optical beacon Cylinder

Amundsen-Scott Station South Pole Optical module AMANDA II Detector

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

The highest energy event (~200 TeV) 300 m

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

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

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

IceCube 1400 m 2400 m AMANDA South Pole IceTop Skiway 80 Strings 4800 PMT Instrumented volume: 1 km3 (1 Gt) IceCube is designed to detect neutrinos of all flavors at energies from 10 7 eV (SN) to eV Talks/Poster by H. Miyamoto this evening

IceCube (1km 3 underground observatory) Sensitive to ~ of the WB bound EHE( ~EeV) -- Almost reachable!  GZK, Z-burst, TD... New Physics? Secondary  /  detection

E µ =10 TeV ≈ 90 hitsE µ =6 PeV ≈ 1000 hits How EHE events look like 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.

EHE (EeV or even higher) Neutrino Events Arriving Extremely Horizontally Needs Detailed Estimation Limited Solid Angle Window (  N A ) -1 ~ 600 (  / cm 2 ) -1 (  /2.6g cm -3 ) -1 [km] Involving the interactions generating electromagnetic/hadron cascades NN  X e + e - RESCEU 2003

e e      e/     Weak Incoming Products Weak Cascades Decay Weak Pair/decay Bremss Pair PhotoNucl. Decay Pair Pair Bremss Decay Weak Decay

RESCEU 2003 Tau(Neutrinos) from    Suppression By  decay Muon(Neutrinos) from   Nadir Angle

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

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

RESCEU 2003 Down-going events dominate… 1400 m 2800 m 11000m UpDown Atmospheric  is attenuated faster…

Flux as a function of energy deposit in km 3 dE/dX~  E  E~  XbE

Flux as a function of energy deposit in km 3 dE/dX~  E  E~  X  E

RESCEU 2003 Intensity of EHE  and  GZK m=4 Z max =4 I  (E>10PeV)I  (E>10PeV) RATE [/yr/ km 2 ] Down Up I  (E>10PeV) Energy Deposit I  (E>10PeV) Energy Deposit Down m=7 Z max =5 Down Atm  [cm -2 sec -1 ]

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

Summary UHE fluxes are constrained by  /CR fluxes. A detection beyond this limit would imply a new class of astronomical objects. EHE  fluxes are constrained by EGRET  /UHECR fluxes and by the synchrotron cooling of  ’ s. The loophole to this bound would be the GZK cosmogenic neutrinos with intensity of ~10 -8 GeV /cm 2 sec sr. 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 of the WB bound. The EHE sensitivity is comparable to the GZK neutrinos fluxes: 3x10 -8 GeV /cm 2 sec sr in 10 years observation. RESCEU 2003