IceCube: Exploring the Universe from the South Pole with high energy neutrinos

1. IceCube: Exploring the Universe from the South Pole with high energy neutrinos Kirill Filimonov for Kurt Woschnagg University of California – Berkeley and the IceCube Collaboration SCAR Open Science Conference - 2010

2. Cosmic rays: a 100 year-old mystery Balloon flights 1911-1913 Victor HessNobel 1936 1 event km -2 yr -1 Equiv. LHCenergy Power law over many decades

3. Cosmic ray – g-ray – Neutrino connection p + p p0 g + g p± p + g m± + nm(nm) e± + ne(ne)+ nm(nm) nm Cosmic accelerator (SNR, AGN, GRB, etc) Cosmicray • Progenitor outflow • Interstellar material • Ambient photon field g g Photons Cosmicray nm ne p, He, ... Neutrinos

4. Neutrinos as Astronomical Messengers B neutrinos neutral - good not absorbed - good and bad! Cosmic accelerator C.R. 1021 g CMBstar-light nm Neutrinos p, He, ... 1018 1015 Energy (eV) Neutrino Photons 1012 Cosmicray 109

5. Neutrino interaction with matter   W N N e, e, W N N e,, e,, Z N N m tracks (nm) Cascades (ne,t CC, ne,m,t NC) E ~ 1 MeV, ~10-43cm2: mean free path is 50 light years in water! E ~ 10 TeV, ~10-34cm2 : small, but manageable with BIG detector… Cascade 1 km n HadronicCascade > 3 kmmuon track  qnm 0.7o qnm ~ ( Em / 10 TeV )0.7 NeutrinoTelescope NeutrinoTelescope

6. Why the South Pole? Antarctic Ice isthe most transparentnatural solid known Average optical ice parameters: labs ~ 110 m @ 400 nm lsca ~ 20 m @ 400 nm

7. Problem: Background rejection Cosmic rays interacting in the atmosphere: high energy muons   Use Earth as a filter to look for neutrinos: throw out down-going tracks

8. All-sky muon flux (IC22, 2008) 106 Muons arXiv:0902.0021 Neutrinos

9. Amundsen-Scott South Pole Station Where are we ? runway South Pole AMANDA-II

10. The IceCube Collaboration University of Alabama University of Alaska, Anchorage University of California, Berkeley University of California, Irvine Clark-Atlanta University Bartol Research Institute, University of Delaware Georgia Institute of Technology University of Kansas Lawrence Berkeley Natl. Laboratory University of Maryland Ohio State University Pennsylvania State University Southern University and A&M College University of Wisconsin, Madison University of Wisconsin, River Falls RWTH Aachen Ruhr-Universität Bochum Universität Bonn DESY, Zeuthen Universität Dortmund MPIfK Heidelberg Humboldt Universität, Berlin Universität Mainz BUGH Wuppertal Stockholms Universitet Uppsala Universitet Vrije Universiteit Brussel Université Libre de Bruxelles Universiteit Gent Université de Mons University of Alberta Chiba University University of Canterbury EPF Lausanne Oxford University University of the West Indies

11. IceCube Detector IceTop: Surface Air Shower Array AMANDA DigitalOpticalModule 1450 m IceCube: (“Main Instrument”) 80 Strings / 60 DOMs each 1 km3 instrumented 324 m 2450 m Deep Core: (Low energy extension)

12. Digitized Waveform Digital Optical Module (DOM) … each DOM, independently collects light signals …time stamps them with 2 nanoseconds precision and sends them to an event builder

14. IceCube Current Status: 79-Strings Taking Data

15. IceCube Selected Results: IC22, IC40

16. IceCube measures the atmospheric neutrino flux predicted: zenith angle number of PMT

17. Atmospheric muon neutrino spectrum • IceCube 22 string analysis • 4492 neutrino events at high purity (>95%)

18. Moon Shadow • Cosmic rays blocked by the moon lead to a point-like deficit in the distribution of down-going muons in the detector.

19. Moon Shadow • Cosmic rays blocked by the moon lead to a point-like deficit in the distribution of down-going muons in the detector. Need high statistics and good angular resolution!

20. Moon Shadow Pointing accuracy is confirmed!

21. Full-sky point source search (IC40) Northern sky: atmospheric neutrino background J. Dumm ICRC 2009 J. Aguilar Vulcano 2010 Southern sky:atmospheric muon backgrounddemand high energy events Preliminary results from 375.5 days exposure 36,900 events: 14,121 upgoing and 22,779 downgoing Maximum p-value 5.2 x 10-6, seen in 18% of randomized sky maps

22. Point Source List

23. Sensitivity to Neutrino Point Sources compilation J. Dumm/T. Montaruli • Includes preliminary limits on 39 pre-selected point sources, largest p-value 62%

24. Ultra-high energy neutrino search (IC22) Phys. Rev. Lett. 103, 221102 (2009) • Look for neutrinos from entire sky by demanding high energies (~PeV) • Reduces data to 1,877 events; max p-value 37.4% – not significant • Also search for correlations with • Auger, HiRes UHE events within 3º radius • Observe 60 events, 43.7 expected • p-value 0.98%, 2.33σ (preliminary)

25. Diffuse All-Flavor Neutrino Flux Limits

26. Indirect Dark Matter Search: the Sun Sensitivity to muon flux from neutralino annihilations in the Sun or the center of the Earth

27. Indirect Dark Matter Search: the Sun

28. Indirect Dark Matter Search: Galactic Halo • No observed excess in IC22 (275 days of data) arXiv0912.5183

29. Summary • IceCube construction is nearly complete • 79 of a planned 86 strings now operating • IceCube is detecting neutrinos: ~ 20 000 neutrinos already observed in two seasons of partially built detector (consistent with expected rate of atmospheric neutrinos) • Results from 22-string and 40-string configurations consistent with atmospheric flux, but several interestingly low p-values • Rich physics is ahead cosmic ray (CR) spectrum,  CR composition  CR anisotropies  atmospheric neutrinos (oscillations,effects of quantum gravity, … )  neutrino point sources gamma ray bursts multimessenger approaches  diffuse  fluxes  dark matter  magnetic monopoles  supernova bursts  shadow of the moon atmosphere physics  glaciology  new technologies for highest energies (radio, acoustics)