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The AMANDA and IceCube 高エネルギー ν 天文学：宇宙探査の窓

The AMANDA and IceCube 高エネルギー ν 天文学：宇宙探査の窓. Physics Motivation AMANDA detector Recent Experimental Results IceCube Project overview and Status EHE Physics Example: Detection of GZK neutrinos. 吉田　滋 (千葉大学理). You cannot expect too many n !. TeV/EGRET observations !!. Cosmic Ray

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The AMANDA and IceCube 高エネルギー ν 天文学：宇宙探査の窓

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  1. The AMANDA and IceCube 高エネルギーν天文学：宇宙探査の窓 • Physics Motivation • AMANDA detector • Recent Experimental Results • IceCube Project overview and Status • EHE Physics Example: Detection of GZK neutrinos 吉田　滋 (千葉大学理)

  2. 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

  3. 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

  4. 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

  5. Shall we Dance?

  6. Where are we ? South Pole Dome road to work AMANDA Summer camp 1500 m Amundsen-Scott South Pole Station 2000 m [not to scale]

  7. “Up-going” (from Northern sky) “Down-going” (from Southern sky) AMANDA-B10 (inner core of AMANDA-II) 10 strings 302 OMs Data years: 1997-99 AMANDA-II 19 strings 677 OMs Trigger rate: 80 Hz Data years: >=2000 Optical Module PMT looking downward PMT noise: ~1 kHz

  8. <labs>~ 110 m @ 400 nm <lsca>~ 20 m @ 400 nm Event detection in the ice O(km) long mtracks South Pole ice: the most transparent natural medium ? event reconstruction by Cherenkov light timing ~15 m • AMANDA-II • mtracks • pointing error : 1.5º - 2.5º • σ[log10(E/TeV)] : 0.3 - 0.4 • coverage : 2p • Cascades (particle showers) • pointing error : 30º - 40º • σ[log10(E/TeV)] : 0.1 - 0.2 • coverage : 4p • cosmic rays (+SPASE) • combined pointing err : < 0.5º • σ[log10(E/TeV)] : 0.06 - 0.1 • Nucl. Inst. Meth. A 524, 169 (2004) cascades a neutrino telescope Qmn0.65o(En/TeV)-0.48 (3TeV<En<100TeV) Longer absorption length → larger effective volume

  9. spectrum up to 100 TeV compatible with Frejus data presently no sensitivity to LSND/Nunokawa prediction of dip structures between 0.4-3 TeV In future, spectrum will be used to study excess due to cosmic ‘s Atmospheric n's in AMANDA-II neural network energy reconstruction regularized unfolding PRELIMINARY measured atmospheric neutrino spectrum 1 sigma energy error

  10. Oscillation in AMANDA‘s range SuperK values: Dm² = 2,4 * 10-3 eV² sin²(2QMix) = 1,0 1 TeV 100 GeV 50 GeV 30 GeV Problem: lower energy threshold ~ 100 GeV - 1 TeV P( nm nm ) 10 GeV positive identification not possible flight length / km 110° 180°

  11. Oscillation in AMANDA‘s range Variation of Dm² (En =100GeV) 10-3eV² significant oscillation in AMANDA‘s range exclusion regions in sin²(2Q)-Dm² -plane 2,4 * 10-3eV² 10-2eV² P( nm nm ) 2,8 * 10-2eV² flight length / km 110° 180°

  12. 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 !

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

  14. 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

  15. Maximum significance 3.4 s compatible with atmospheric n ~92% n telescope : point source search Preliminary • Search for clustering in northern hemisphere • compare significance of local fluctuation to • atmospheric n expectations • un-binned statistical analysis • no significant excess 2000-2003 3369 n from northern hemisphere 3438 n expected from atmosphere also search for neutrinos from unresolved sources

  16. Extend this information to the AMANDA exposure time, caveat: g-rays observation are generally very short and for limited periods… Tibet data quite cover the (HEGRA) High period Second Assumption: use X-ray data to define relative High/Low time for the whole time 2000/2003 AMANDA observational time High state/total time: ~210/807 or also ~1 year/4 years of AMANDA exposure

  17. Fit of the measured spectrum from HEGRA (Low) Allowed range for the emitted flux AMANDA sensitivity Low state: can be compared to our best upper limit (sensitivity shown here) about factor 2 Correction for extra-galactic g absorption¶: TeV g-ray spectra are modified by red-shift dependent absorption by intergalactic IR-UV background ¶O.C.De Jager & F.W.Stecker, Astrophy.J. 566 (2002), 738-743

  18. Fit of the measured spectrum from HEGRA (Low) Allowed range for the emitted flux AMANDA sensitivity (NB: this under the assumption that the source would show ~ 800 days of high state!) High state: can be compared to the AMANDA sensitivity for ~ 200 days of live time (1 year exposure) Sensitivity n/g~1 BUT without accounting for oscillations (a factor 2 in the n flux should be added!!) Current best estimate

  19. Search for  correlated with GRBs -1 hour +1 hour 10 min Blinded Window Background determined on-source/off-time Background determined on-source/off-time Time of GRB(Start of T90 ) Low background analysis due to space and time coincidence! PRELIMINARY • GRB catalogs: • BATSE, IPN3 & GUSBAD • Analysis is blind: • finalized off-source (± 5 min) with MC simulated signal • BG stability required within ± 1 hour • Muon effective area (averaged over zenith angle) 50,000 m2 @ PeV (BT = BATSE Triggered BNT = BATSE Non-Triggered New = IPN & GUSBAD) 97-00 Flux Limit at Earth*: E2Φν≤4·10-8GeV cm-2 s-1 sr-1 *For 312 bursts w/ WB Broken Power-Law Spectrum (Ebreak= 100 TeV, ΓBulk= 300)

  20. WIMP annihilations in the center of Earth Sensitivity to muon flux from neutralino annihilations in the center of the Earth: PRELIMINARY Muon flux limits Look for vertically upgoing tracks Eμ > 1 GeV NN optimized (on 20% data) to - remove misreconstructed atm. μ - suppress atmospheric ν - maximize sensitivity to WIMP signal Combine 3 years: 1997-99 Total livetime (80%): 422 days Disfavored by direct search (CDMS II) No WIMP signal found Limit for “hardest” channel:

  21. WIMP annihilations in the Sun Increased capture rate due to addition of spin-dependent processes Sun is maximally 23° below horizon Search with AMANDA-II possible thanks to improved reconstruction capabilities for horizontal tracks Exclusion sensitivity from analyzing off-source bins 2001 data 0.39 years livetime PRELIMINARY Muon flux limits Eμ > 1 GeV No WIMP signal found Best sensitivity (considering livetime) of existing indirect searches using muons from the Sun/Earth

  22. AMANDA as supernova monitor AMANDA-II AMANDA-B10 IceCube 30 kpc ~MeV Bursts of low-energy (MeV) νe from SN ► simultaneous increase of all PMT count rates (~10s) Since 2003: SNDAQ includes all AMANDA-II channels Recent online analysis software upgrades • can detect 90% of SN within 9.4 kpc • less than 15 fakes/year can contribute to SuperNova Early Warning System (with Super-K, SNO, Kamland, LVD, BooNE) coverage B10: 70% of Galaxy A-II: 95% of Galaxy IceCube: up to LMC Analysis of 200X data in progress

  23. The IceCube Neutrino Telescope • Project overview and Status • EHE Physics Example: Detection of GZK neutrinos

  24. Who are we ? Bartol Research Inst, Univ of Delaware, USA Pennsylvania State University, USA University of Wisconsin-Madison, USA University of Wisconsin-River Falls, USA LBNL, Berkeley, USA UC Berkeley, USA UC Irvine, USA Univ. of Alabama, USA Clark-Atlanta University, USA Univ. of Maryland, USA IAS, Princeton, USA University of Kansas, USA Southern Univ. and A&M College, Baton Rouge Chiba University, Japan University of Canterbury, Christchurch, New Zealand Universidad Simon Bolivar, Caracas,Venezuela Université Libre de Bruxelles, Belgium Vrije Universiteit Brussel, Belgium Université de Mons-Hainaut, Belgium Universität Mainz, Germany DESY-Zeuthen, Germany Universität Wuppertal, Germany Uppsala Universitet, Sweden Stockholm universitet, Sweden Kalmar Universitet, Sweden Imperial College, London, UK University of Oxford, UK Utrecht University, Utrecht, NL

  25. First year deployment (Jan 2005) 4 IceCube strings (240 OMs) 8 IceTop Tanks (16 OMs) IceTop 160 tanks frozen-water tanks 2 OMs / tank 1200 m IceTop IceCube AMANDA IceCube 80 strings 60 OMs/string 17 m vertical spacing 125 m between strings IceTop Tank deployed in 2004 10” Hamamatsu R-7081

  26. 9 hours 6 hours Road to South Pole

  27. 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.

  28. Digital Optical Module (DOM) HV Base “Flasher Board” Main Board (DOM-MB) 10” PMT 13” Glass (hemi)sphere

  29. ATWD 300MHz 14 bits. 3 different gains (x15 x3 x0.5) Capture inter. 426nsec 10 bits FADC for long duration pulse. Capture Waveform information (MC) nt E=10 PeV String 5 String 4 String 3 String 1 String 2 Events / 10 nsec 0 - 4 µsec

  30. Assembly Calibration Assembly Calibration Electronics Calibration Screening. World-wide DOM collaboration Stockholm Wisconsin LBL DESY Chiba

  31. Selection criteria (@ -40 °C) Noise < 300 Hz (SN, bandwidth) Gain > 5E7 at 2kV (nom. 1E7 + margin) P/V > 2.0 (Charge res.; in-situ gain calibration) Notes: Only Hamamatsu PMT meets excellent low noise rates! Tested three flavors of R7081. Photomultiplier:HamamatsuR7081-02 (10”, 10-stage, 1E+08 gain)

  32. SPE Charge Spectrum

  33. Setup photo

  34. Expected Data Rates • PMT noise rate of 1 kHz is expected • "Scintillation" of glass introduces correlations! • Two DOMs/twisted pair ( $, kg, flights,...) • Rates/pair (bits/s) for coincidence mode (with zero suppression and compression) • None: 18 kbytes/s x 2 x 10 = ~400 kbits/s • Soft: 6-8 kbytes x 2 x 10 = ~160 kbits/s • Hard: <1 kbyte/s x 2 x 10 = ~20 kbits/s • Demonstrated in the lab: 1 Mbit/s

  35. IceCube Software

  36. ROMEO – Optical detector simulator • ROOT Ttask base • Full detector simulation

  37. , t , n m JULIeT – Particle Propagator Monte-Carlo Simulation Numerical Calculation

  38. Angular resolution as a function of zenith angle Waveform information not used. Will improve resolution for high energies ! 0.8° 0.6° • above 1 TeV, resolution ~ 0.6 - 0.8 degrees for most zenith angles

  39. Energy Spectrum Diffuse Search Blue: after downgoing muon rejection Red: after cut on Nhit to get ultimate sensitivity

  40. HEAPA 2004 Project status • Startup phase has been approved by the U.S. NSB and funds have been allocated. • 100 DOMs are produced and being tested this year. • Assembling of the drill/IceTop prototypes is carried out at the pole lastseason. • Full Construction start in 04/05 (this year!!); takes 6 years to complete. • Then 16 strings per season, increased rate may be possible.

  41. Right now at the pole

  42. HEAPA 2004 GZK EHEn detection • What is the GZK mechanism? • EHE n/m/t Propagation in the Earth • Expected intensities at the IceCube depth • Atmospheric m – background • Event rate

  43. UHE (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-

  44. 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

  45. Atmospheric muon! – a major backgrond But so steep spectrum Upward-going Downward going!! HEAPA 2004

  46. 11000m 2800 m 1400 m Down-going events dominate… Atmospheric m is strongly attenuated… Up Down HEAPA 2004

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

  48. The uncertainty ~3 orders Need for accelerator data extrapolation Crossover between 40TeV and 3 PeV AMANDA II (neutrinos) Uncertainty in Prompt Lepton Cross Sections ZhVd

  49. Constraining Charm Neutrino models by analysis of downgoing Muon Data AMANDA II (neutrinos) • Very preliminary sensitivity on ZHV-D model • Systematics to be well understood • Potential to set a more restrictive limit than neutrino diffuse analyses ZHVd AMANDA II (muons)

  50. IceCube EHE n Sensitivity 90% C.L. for 10 year observation • Published in Phys. Rev. D S.Yoshida, R.Ishibashi, H,Miyamoto, PRD 69 103004 (2004)

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