neutrino astronomy francis halzen University of Wisconsin

Transcription

1 neutrino astronomy francis halzen University of Wisconsin

2 menu neutrino astronomy cosmic ray accelerators and neutrinos: km 3 neutrino detectors Amanda and Antares: first generation detectors ~ km 3 IceCube results: neutrino astronomy muon astronomy (?) dark matter search

3 M. Markov 1960 B. Pontecorvo M.Markov : we propose to install detectors deep in a lake or in the sea and to determine the direction of charged particles with the help of Cherenkov radiation.

4 shielded and optically transparent medium muon interaction lattice of photomultipliers neutrino

5 menu neutrino astronomy cosmic ray accelerators and neutrinos: km 3 neutrino detectors Amanda and Antares: first generation detectors ~ km 3 IceCube results: neutrino astronomy muon astronomy (?) dark matter search

6 particles produced in a nuclear reactions produce blue light in water Copyright 2001 Purdue University

7 Cherenkov light

8 cherenkov radiation: particle s speed exceeds the speed of light

9 photomultiplier tube

10 2008 ANTARES

11 2000 AMANDA South Pole Dome 1500 m 2000 m [not to scale] Amundsen-Scott South Pole station

12 AMANDA proof of concept neutrino interaction muon track ν μ + N μ+ X

13 atmospheric neutrinos high energy cosmic ray π μ ν μ 15 Km

14 detector measures the atmospheric neutrino flux predicted: method validated ~ 100 TeV zenith angle number of PMT

15 energy estimation muon track π γ bremsstrahlung e + e - photo-nuclear pair-creation convert light emitted to estimate of the muon energy ( number of optical modules, number of photons, de/dx, Sean Grullon

16 menu neutrino astronomy cosmic ray accelerators and neutrinos: km 3 neutrino detectors Amanda and Antares: first generation detectors ~ km 3 IceCube results: neutrino astronomy muon astronomy (?) dark matter search

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18 drilling and deployment to 2500 m in less than 2 days 3.5 cm/second 18

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20 photomultiplier starts its journey to 2500 m the IceCube project transforms a billion tons of ice into a particle physics detector

21 start million pounds of cargo C-130 planes: > 50 flights IceCube

22 IceCube Site 5 megawatt power plant

23 one of 21 drill modules arrive in antarctica

24 Hose winch Drill tower Hot water generator IceTop Tanks 5 megawatt hot water drilling system

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26 125 m 26

27 IceCube deployments Counting house: commissioned in January 2007 Completion 2011 : 80 strings 60 modules each 17m between modules 125m between strings 1 km³ ; ~1GTon : 13 strings : 8 strings : 1 string optical modules in ice: AMANDA 677 IceCube 1320

28 since jan out of : 18 Strings : 13 Strings : 18+1 Strings : 1 String : 8 Strings 1450 m 2450 m

29 IceCube neutrinos (40 out of 80 strings) operated for 276 days collected 10,000 neutrinos

30 one in 10 6 muon tracks is produced by a neutrino

31 challenge : p separate neutrinos (filtered by the Earth) from down- going cosmic ray muons at a level of much less than one per million ν μ

32 challenge : separate neutrinos filtered by the Earth from down- going cosmic ray muons at a level of much less than one per million

33 IceCube background: downgoing cosmic ray muons ~ 2000 per second signal: upgoing muons initiated by neutrinos ~ 10 per hour

34 within trigger time window down down down up

35 upcoming neutrinos downgoing muons

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37 IceCube then and now PeV: x2 EeV: x3 IceCube neutrino area predicted performance (blue) Astroparticle Physics 20, 507 (2004)

38 menu neutrino astronomy cosmic ray accelerators and neutrinos: km 3 neutrino detectors Amanda and Antares: first generation detectors ~ km 3 IceCube results: neutrino astronomy muon astronomy (?) dark matter search

39 atmospheric neutrinos: ultimate background ν μ,(e,τ) HE Cosmic Particle (~PeV) μ ν μ Angular Resolution ν μ < 1

40 AMANDA II 2000 directions of ~ 600 neutrinos

41 IceCube supersedes AMANDA by superior angular resolution IceCube 22 strings: 5114 neutrinos in 276 days

42 the hottest spot location is: Ra 153.5, Dec 11.5 events: 11 background: 3.3 -log 10 (p-value) : 6.14 (4.8 sigma) happens in 63 out of 10 4 scrambled maps, or the probability is ~ 0.01

43 intermezzo on point source search

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45 looking up background of atmospheric muons instead of neutrinos reduced by 10-5

46 looking up

47 40 strings for ½ year ~ ¼ km 3 yr of data 7 events with probability pre-trial not significant

48 diffuse flux excess of extra-terrestrial neutrinos (E -2 ) over atmospheric neutrinos (E -3.7 ) at the high-energy tail of an energy distribution

49 neutrinos associated with extragalactic cosmic rays IceCube AMANDA IceCube 22 strings

50 grb (3.84 sigma, 2.81 sigma post trial) Parameter Value Parameter Value GRB zenith GRB azimuth zenith azimuth angle difference to GRB 5.44 paraboloid sigma 1.70 rlogl 7.20 log10(hits) 2.93 log10(charge) 3.46 nchannel 143 svm classifier Time of event GRB T100-3 to 33 next 40 strings : 1.5 events from 86 bursts

51 with unbiased surveys expect the unexpected the cosmic ray sky!

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53 first view of the Southern hemisphere in TeV muons h -90 significance for each bin value from the average bin value for each declination

54 is this real? is the background more interesting? Tibet array: northern hemisphere

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56 expect the unexpected with unbiased surveys IceCube & Tibet Array IceCube & Milagro

57 significance maps for two energy bins h -90 significance map for median energy significance map for median energy 12.6 TeV 126 TeV not the sun! sturcture of galactic magnetic field (large scale)? nearby sources (small scale)?

58 vela? geminga?

59 particle physics with one million atmospheric neutrinos (10 GeV ~ 1 PeV) deep core ( < 10 GeV, oscillations, hierarchy ) measurement of the high-energy neutrino cross section neutrino hierarchy with DeepCore quantum decoherence test special and general relativity with new precision search for magnetic monopoles search for dark matter search for topological defects and cosmological remnants search for non-standard model neutrino interactions Planck scale physics with GRBs particle physics with MeV neutrinos from supernova explosion in the galaxy ( 2 megaton )

60 to 10 GeV with DeepCore tau electron muon

61 bigger and better detector LED flasher board main board HV board

62 digital optical module R cm OB-LED Delay Trigger (2) x 2.6 x 9 x16 x2 x0.25 MUX Pulser ATWD ATWD fadc 10b 10b 10b 40 MHz FPGA DP Ram CPU 10b 8b ADC DAC +/-5V, 3.3V, 2.5V, 1.8V Configuration Device 32b LPF SDRAM 1 megabaud DOR DC-DC 8Mbit 16Mb (n+1) (n 1) LC 20 MHz SDRAM 16Mb Oscillator Corning Frequency Ctl (was Toyocom) Monitor & Control DACs & ADCs 8b, 10b, 12b CPLD PMT Power 8b 16b Flash Flasher Board Flash 4Mb 4Mb 64 Bytes

63 The Digital Optical Module (DOM) Onboard capture of PMT waveforms 300 MHz for ~400 ns with custom chip 40 MHz for 6.4 µsec with comm. fast ADC Digitized Waveform Absolute timing resolution < 2 ns (RMS) Dynamic range ~1000 p.e./10 ns Deadtime < 1% Noise rate ~700 Hz (260 Hz w / artif. deadtime) Failure rate < 1%

64 AMANDA/IceCube as MeV ν detector PMT noise low (~ 300 Hz) ice uniformly illuminated detect correlated rate increase on top of PMT noise

65 hierarchy with galactic supernova explosion

66 WIMPs captured in the sun χ annihilate into neutrinos ν μ n DETECT χ + χ W + W ν +... b + b ν +...

67 atmospheric neutrino events the sun

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69 sensitivity to wimp dark matter : spin-dependent interactions ) 2 Neutralino-proton SD cross-section (cm < Ω χ h < σ < σlim CDMS(2008)+XENON10(2007) SI SI σ < 0.001xσlim CDMS(2008)+XENON10(2007) -33 SI SI 10 CDMS (2008) COUPP (2008) IceCube-80+DeepCore 1800d sens. (hard) KIMS (2007) SUPER-K IceCube (soft) IceCube (hard) AMANDA 7y (hard) AMANDA 7y (soft) Neutralino mass (GeV) 4

70 conclusions IceCube is taking data with a ¾ km 3 instrumented volume integrated exposure reaches 1 km 2 year this year Antares TDR for KM3NeT this year