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NeutrinoAstrophysicsHEAP2011.ppt - IceCube Docushare

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					High-energy Neutrino Astrophysics
 with IceCube Neutrino Observatory




       Shigeru Yoshida
     Department of Physics
       Chiba University
The IceCube Neutrino Observatory


                                                                    Configuration
                                                                     chronology
                     2004: Project Start       1 string             2006: IC9
                     2011: Project completion 86 strings            2007: IC22
                                                                    2008: IC40
                                                                    2009: IC59
                                        8
                                                                    2010: IC79
                                                                    2011: IC86


                      DeepCore
                      8 strings – spacing optimized for lower energies
                      480 optical sensors




                                                                         PMT

                                        Digital Optical Module (DOM)
 The IceCube Collaboration
  http://icecube.wisc.edu
  36 institutions, ~250 members

Canada
University of Alberta                   Sweden                 Germany
                                        Uppsala Universitet    Universität Mainz
                                        Stockholms Universitet DESY-Zeuthen
US                                                             Universität Dortmund
Bartol Research Institute, Delaware                            Universität Wuppertal
Pennsylvania State University           UK                     Humboldt-Universität zu Berlin
University of California - Berkeley     Oxford University      MPI Heidelberg                Japan
University of California - Irvine                              RWTH Aachen
                                                                                             Chiba University
Clark-Atlanta University                                       Universität Bonn
University of Maryland                                         Ruhr-Universität Bochum
University of Wisconsin - Madison
University of Wisconsin - River Falls                    Belgium
Lawrence Berkeley National Lab.                          Université Libre de Bruxelles
University of Kansas                                     Vrije Universiteit Brussel
Southern University, Baton Rouge                         Universiteit Gent
University of Alaska, Anchorage                          Université de Mons-Hainaut
University of Alabama, Tuscaloosa
Georgia Tech                                             Switzerland
Ohio State University                                    EPFL, Lausanne

Barbados
University of West Indies                                                                          New Zealand
                                                                                            University of Canterbury
                                           ANTARCTICA
                                           Amundsen-Scott Station
         DOM
Digital Optical Module

                         HV Base


                      “Flasher Board”
                     Main Board
                     (DOM-MB)

                         10” PMT

                         13” Glass
                         (hemi)sphere
                      Neutrino Detection Principle
Observe the charged secondaries
via Cherenkov radiation detected
by a 3D array of optical sensors

   νl                  l, νl
               W, Z
                       hadronic
                       shower



Need a huge volume (km3)
of an optically transparent                g
detector material

Antarctic ice is the                                 m
most transparent
natural solid known
(absorption lengths up 200 m)                            n
        Note: Different dataset
 IC86 = full IceCube (2011~)
         IceCube




IC79 (2010-2011)      IC59 (2009-2010)   IC40 (2008-2009)   IC22 (2007-2008)
  IceCube                  IceCube          IceCube             IceCube
                 Point Source Search
signal + background
     hypothesis
                                        nm  m base
          vs




                               North
                                       North      South
  background only
   null hypothesis




                       m
 Note:
 It’s ALL SKY survey


                           m
                               CR
                                   n skymap
                                                                IceCube + IceCube

                                                                   IceCube Preliminary
                                       Hottest spot: RA 75.45 Dec -18.15 -log(p)=4.65
up-going m’s w/ atmospheric n BG                      ~36 % probability with trial factors




down-going PeV m’s w/ cosmic-rays BG
                           GRB Search
                                                               nm  m base
                           T0: From a satellite GCN
                                                                      Zenith > 85 deg.




     Off-time                     On-time                            Off-time
Precursor (~100 s)                           GRB n modeling – individual GRB bases
                                                Guetta et al Astropart.Phys. 20 (2004) 429
Prompt
Model Independent (24 h)
Background (full year)
              No association of n’s
                  with GRB..
                                         Model-dependent limits




                                              IceCube

                                             IceCube
                                                +
                                             IceCube




We are on the way to indicate GRBs are
unlikely to be a major UHECR origin.
Searches for a Diffuse Neutrino Flux
Diffuse Flux = effective sum from all (unresolved) extraterrestrial sources (e.g., AGNs)
Possibility to observe diffuse signal even if flux from any individual source is too weak for
detection as a point source

                                            Search for excess of astrophysical
                                            neutrinos with a harder spectrum than
                                            background atmospheric neutrinos

                                                     Atmospheric n, m

                                                              Harder Spectrum n (E-2)
Astro. n
                                                                 Energy



                                            Advantage over point source search:
                                             can detect weaker fluxes

                                            Disadvantages:
 Atm. n                                      high background
                                             must simulate background precisely

                                            Sensitive to all three neutrino flavors in
                                            principle
                     Atm. m
                 Diffuse n limit                nm  m base
                       30 TeV ~ 10 PeV
        Now below the Waxman-Bahcall limit

   nm only




                                         Waxman-Bahcall bound

             IceCube
                IC40                     (theoretical reference
                                         estimated from cosmic rays flux
                                         assuming optically thin sources)




PRD 84 082001 (2011)
              Diffuse n limit
                   30 TeV ~ 10 PeV      All flavor base
        By looking for cascade events




                            IceCube




                          IceCube
                           (expected)




PRD 84 072001 (2011)
                               GZK n search
Energy Dist. @ IceCube Depth
                               Detection Principle     Zenith Dist. @ IceCube Depth




through-going track
      Secondary m and t from n               And tracks arrive horizontally
                 Sensitive to   nm nt
starting track/ cascade                              Yoshida et al PRD 69 103004 (2004)
      Directly induced events from n
                 Sensitive to   ne nm nt
                                              The detailed description available in
                                              PRD 82 072003 (2010)

                  GZK n search
                   Detection Principle
                              Energy
                   NPE (total # of photoelectrons)

                   Look for luminous (high NPE)
                         horizontal events


Experimental verification                                    Data

                        MC overestimates
                         NPE by ~18%                            MC


                        Sys. error
                          ~ 7% in SIG rate
                         ~ 50% in BG rate
                        GZK n search                              PRD 83 092003 (2011)
                All flavor (ne + nm + nt) limits    Systematic errors included



                  IceCube

              IceCube




          IceCube
           (expected)




The world’s best all-flavor n upper limits to date from 106 to 1010 GeV
                Expected EHE signal events                                                                           PRD 83 092003 (2011)
                                                                                                                   The full IceCube
                                                                            IceCube
                                                                           The half IceCube
                               Models                                                                                # of events
                                                                              # of events
                                                                                                                      (3 years)
         GZK1 (Yoshida et al) *                                      0.57                                 3.1
         GZK2 Strong Evol. (Sigl) **                                 0.91 (C.L 53.4%)                     4.9
         GZK3 (ESS with WL=0.0) ***                                  0.29                                 1.5

         GZK4 (ESS with WL=0.7) ***                                  0.47                                 2.5
         GZK5 (Ahlers max) ****                                      0.89 (C.L 52.8%)                     4.8
         GZK6 (Ahlers best fit) ****                                 0.43                                 2.3
         Z-Burst #                                                   1.03 (C.L 55.7%)                     5.1
         Top Down(SUSY) ##                                           5.68 (C.L 99.6%)                     31.6
         Top Down(QCD) ###                                           1.19 (C.L 66.4%)                     6.3
         W&B(evol) ^                                                 3.7                                  24.5
         W&B(no evol) ^                                              1.1                                  5.5


*Yoshida et al The ApJ 479 547-559 (1997), **Kalahsev et al , Phys.Rev.Rev. D 66 063004 (2002), ***Engel et al, Phys. Rev. D, 64(9):093010, 2001, ****Ahlers
et al, Astropart. Phys. 34 106-115 (2010) #Yoshida et al, Phys.Rev.Lett. 81 5505 (1998),##Sigl et al , Phys.Rev.Rev. D 59 043504 (1998), ^Razzaque et
al(2003)
                                                                     IceCube

                The Highest NPE event


         Keep
Cut




       This event

p-value for the background hypothesis ~0.2%   • Detected in 2008 December 8th
                  (posteriori)                • NPE 2.55x105 photo-electrons
                                              • Zenith 64.7 deg



      Aya Ishihara (Chiba)
Diffuse n limits – global picture


As of 2011 reported                                        ANITA
                                            RICE   Auger
All “IceCube” is “a half IceCube”
with 2008-9 configuration
        IceCube                                                    HiRes



    ANTARES 2010                                            IceCube EHE
                                                                   PRD 83 092003 (2011)
                                          IceCube UHE
     PRD 84 082001 (2011)   IceCube VHE

 1TeV                       1PeV                     1EeV                    1ZeV
                     nN CC cross section bound
                 with the IceCube 2008 observation

                                          1 EeV ~ s  40 TeV


Flux of cosmic n
                                           snNSM calculated by
(“Beam Intensity”)                         Cooper-Sarkar & Sarkar
                                           JHEP01:075 (2010)
                         Standard Model
                         predictions




        S.Yoshida PRD 82 103012 (2010)
   Fluxes at the IceCube depth
      Black Hole evaporation scenario
                      J.Alvarez-Muniz et al PRD 65, 103002 (2002)




                                          x=1

                                                        SM




S.Yoshida PRD 82 103012 (2010)
                         Number of events
                       in the IceCube 2008 run
                     Black Hole evaporation scenario




                                                   90 % C.L. (2.44 events)
Cosmic n intensity




                                        Excluded


                                        Expected
@ 1 EeV




       S.Yoshida PRD 82 103012 (2010)
               MSSM Neutralino Dark
                     Matter
      c




                                                                                 North
                                                 n
     cc  bb ,t +t  ,W +W  , ...  n s


Spin Dependent cross-section: Abundant hydrogen in Sun suitable              m
                                for spin dependent cross-section measures
Spin Independent cross-section: Many direct dark matter searches sensitive       CR
                   Dark matter searches:
                       Solar WIMPs
  cc  bb ( soft ), W +W  (hard ), ...  n s

• Determine the muon
  flux from the direction of
  the Sun
   •   A few to 103 events per year
   •   GeV to TeV energies
                                                                   IceCube

• Limit the neutrino-
  induced muons from
  WIMP annihilation                                                IceCube
• A strong limit on SD
  cross-section and good              Phys. Rev. Lett. 102 201302 arXiv:0902.2460
  potential                           IceCube Preliminary
      Dark Matter from the Galactic Halo
                                Dark matter density profile
                                 Dark matter model
dn  s A         Rsc  dNn
                          2
            J ( )       sc        IceCube IC22 (275 days)
 dE    2            4 m dE
                          c
                           2
                                      found no excess
                                       PRD 84 022004 (2011)
            Measure or limit

				
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posted:4/5/2013
language:English
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