IceCube Results & PINGU Perspectives

Transcription

1 1 IceCube Results & PINGU Perspectives D. Jason Koskinen for the IceCube-PINGU Collaboration September 2014 Neutrino Oscillation Workshop Otranto, Lecce, Italy

2 2 IceCube Detector ~1km 3 of instrumented ice Uses ~5k optical sensors across 86 vertical strings to detect Cherenkov radiation Deployed km below the surface ν IceCube DOM

3 2 IceCube Detector ~1km 3 of instrumented ice Uses ~5k optical sensors across 86 vertical strings to detect Cherenkov radiation Deployed km below the surface νµ IceCube DOM

4 3 Event Movie

5 3 Event Movie

6 4 Track topology (e.g. induced by muon neutrino)! Good pointing, Lower bound on energy for through-going events νμ + N μ + X Track νx + X νx + X Cascade Cascade topology (e.g. induced by electron neutrino)! Good energy resolution, 15% Some pointing, 10-15

7 4 Track topology (e.g. induced by muon neutrino)! Good pointing, Lower bound on energy for through-going events νμ + N μ + X Track νx + X νx + X Cascade Cascade topology (e.g. induced by electron neutrino)! Good energy resolution, 15% Some pointing, 10-15

8 5 IceCube Classic

9 6 High Energy Starting Events (HESE)

10 6 High Energy Starting Events (HESE) Follow-up to observation of two events > 1 PeV in IceCube search for Ultra-High Energy (GZK) neutrinos

11 6 High Energy Starting Events (HESE) Follow-up to observation of two events > 1 PeV in IceCube search for Ultra-High Energy (GZK) neutrinos Use outermost layer of IceCube as a veto region Identifies possible muon background Enforces neutrino interaction containment

12 6 High Energy Starting Events (HESE) Follow-up to observation of two events > 1 PeV in IceCube search for Ultra-High Energy (GZK) neutrinos Use outermost layer of IceCube as a veto region Identifies possible muon background Enforces neutrino interaction containment Focused on brightest events with > 6000 photoelectrons

13 7 High Energy Neutrinos Ultra-high energy IceCube (GZK) astrophysical search found 2 anomalous background events in 2 years of data 1.04±0.16 PeV 1.14±0.17 PeV

14 7 High Energy Neutrinos Ultra-high energy IceCube (GZK) astrophysical search found 2 anomalous background events in 2 years of data 1.04±0.16 PeV 1.14±0.17 PeV

15 8 3-year HESE Result! 36(+1) events total! 8.4 ± 4.2 atm. muons atm. neutrinos 5.7σ rejection of only atmospheric neutrino flux! Consistent with 1:1:1 flavor ratio

16 9 HESE-III Sky Map arxiv: No significant evidence for clustering

17 10 Natural Neutrino Flux (>1 GeV)

18 10 Natural Neutrino Flux (>1 GeV) Combination of conventional neutrino, high energy astrophysical, and possible prompt neutrinos from charm hadron decay

19 10 Natural Neutrino Flux (>1 GeV) Cosmic Ray Combination of conventional neutrino, high energy astrophysical, and possible prompt neutrinos from charm hadron decay

20 10 Natural Neutrino Flux (>1 GeV) Cosmic Ray X Charm Hadron Combination of conventional neutrino, high energy astrophysical, and possible prompt neutrinos from charm hadron decay

21 10 Natural Neutrino Flux (>1 GeV) Cosmic Ray X X Charm Hadron Neutrino Combination of conventional neutrino, high energy astrophysical, and possible prompt neutrinos from charm hadron decay

22 11 Prompt Neutrino Flux Cosmic Ray X X Charm Hadron Neutrino

23 11 Prompt Neutrino Flux Cosmic Ray X X Charm Hadron Neutrino Prompt flux more closely follows the incident CR energy spectrum (E -2 ) than the conventional neutrino spectrum (E -2.7 to -3.7 )

24 11 Prompt Neutrino Flux Cosmic Ray X X Charm Hadron Neutrino Prompt flux more closely follows the incident CR energy spectrum (E -2 ) than the conventional neutrino spectrum (E -2.7 to -3.7 ) Prompt ν e versus ν µ channel is advantageous due to conventional ν µ bkg

25 12 Prompt Component

26 12 Prompt Component Prompt can be constrained by flux in the TeV range Higher energy is dominated by astrophysical flux Lower energy is dominated by conventional flux (pion/kaon decay)

27 12 Prompt Component Prompt can be constrained by flux in the TeV range Higher energy is dominated by astrophysical flux Lower energy is dominated by conventional flux (pion/kaon decay) Northern vs. Southern sky comparison weakly breaks the degeneracy between the astrophysical and prompt flux

28 13 A Prompt Result Atm. Neutrinos Atm. Muons Places upper limits on some prompt models (<1.4 ERS model)

29 14 Fundamental Physics with DeepCore

30 15 DeepCore scattering

31 15 DeepCore Low-energy extension Closer instrumentation Clearer Ice Higher efficiency PMTs scattering

32 15 DeepCore Low-energy extension Closer instrumentation Clearer Ice Higher efficiency PMTs Use surrounding IceCube as a veto volume scattering

33 DeepCore Low-energy extension Closer instrumentation Clearer Ice Higher efficiency PMTs Use surrounding IceCube as a veto volume scattering Oscillation Physics νµ disappearance ντ appearance* *Covered later for PINGU 15

34 16 Neutrino Oscillation νµ νµ νµ ~12,700km νµ νµ Mena, Mocioiu & Razzaque, Phys. Rev. D78, (2008) ντ appearance νµ disappearance IceCube DeepCore

35 16 Neutrino Oscillation Northern Hemisphere νµ oscillating over one earth radii produces νµ (ντ) oscillation minimum (maximum) at ~25 GeV νµ νµ νµ ~12,700km νµ νµ Mena, Mocioiu & Razzaque, Phys. Rev. D78, (2008) ντ appearance νµ disappearance IceCube DeepCore

36 16 Neutrino Oscillation Northern Hemisphere νµ oscillating over one earth radii produces νµ (ντ) oscillation minimum (maximum) at ~25 GeV Beam never turns off νµ νµ νµ ~12,700km νµ νµ Mena, Mocioiu & Razzaque, Phys. Rev. D78, (2008) ντ appearance νµ disappearance IceCube DeepCore

37 16 Neutrino Oscillation Northern Hemisphere νµ oscillating over one earth radii produces νµ (ντ) oscillation minimum (maximum) at ~25 GeV Beam never turns off Samples all terrestrial baselines νµ νµ νµ ~12,700km νµ νµ Mena, Mocioiu & Razzaque, Phys. Rev. D78, (2008) ντ appearance νµ disappearance IceCube DeepCore

38 17 νµ Disappearance in DeepCore High-purity analysis selected 5293 events over MC Expectation (3-yr) Type Osc. No Osc νµ ντ νe 418 νnc Atm. µ 54 Total

39 18 Oscillation Contours

40 19 Next?

41 20 Two Directions

42 20 Two Directions Higher energy Point sources Neutrino flavor ratios HEX - High Energy Extension

43 20 Two Directions Higher energy Point sources Neutrino flavor ratios HEX - High Energy Extension Lower Energy - just past DeepCore at the O(1) GeV sensitivity: Resolve the ordering of the Neutrino Mass Hierarchy Improve neutrino oscillation ντ appearance non-maximal θ 23 GeV mass Dark Matter PINGU

44 20 Two Directions Higher energy Point sources Neutrino flavor ratios HEX - High Energy Extension Lower Energy - just past DeepCore at the O(1) GeV sensitivity: Resolve the ordering of the Neutrino Mass Hierarchy Improve neutrino oscillation ντ appearance non-maximal θ 23 GeV mass Dark Matter PINGU

45 21 PINGU

46 22 Precision IceCube Next Generation Upgrade IceCube DeepCore PINGU Letter of Intent - arxiv:

47 22 Precision IceCube Next Generation Upgrade Use existing and familiar technology to infill DeepCore IceCube DeepCore PINGU Letter of Intent - arxiv:

48 22 Precision IceCube Next Generation Upgrade Use existing and familiar technology to infill DeepCore IceCube Improve rejection of cosmic ray muon background DeepCore PINGU Letter of Intent - arxiv:

49 22 Precision IceCube Next Generation Upgrade Use existing and familiar technology to infill DeepCore IceCube Improve rejection of cosmic ray muon background DeepCore Primary physics goal is resolving neutrino mass hierarchy PINGU Letter of Intent - arxiv:

50 23 PINGU Simulation Event DeepCore 9.28 GeV Neutrino, 4.9 GeV muon, 4.5 GeV cascade DeepCore+PINGU

51 23 PINGU Simulation Event DeepCore 9.28 GeV Neutrino, 4.9 GeV muon, 4.5 GeV cascade DeepCore+PINGU

52 23 PINGU Simulation Event DeepCore 9.28 GeV Neutrino, 4.9 GeV muon, 4.5 GeV cascade ~20 vs. ~50 Hit Modules DeepCore+PINGU

53 24 PINGU Neutrino Mass Hierarchy

54 24 PINGU Neutrino Mass Hierarchy 1 1

55 24 PINGU Neutrino Mass Hierarchy

56 24 PINGU Neutrino Mass Hierarchy Inverted/Normal hierarchy has up to a 20% difference in oscillation probability for specific energies and zenith angles (baselines)

57 25 Neutrino Mass Hierarchy by Eye Track-Like Events (mainly CC νµ+νµ) Preliminary 1-year exposure

58 26 Systematics Several of the main systematics have been examined Preliminary

59 27 Mass Hierarchy Bottom Line

60 28 ντ Appearance in PINGU

61 28 ντ Appearance in PINGU Direct measure of Uτ3 2

62 28 ντ Appearance in PINGU Direct measure of Uτ3 2 (GeV) E ν livetime: 1 year PINGU preliminary N all flavours -N νe +ν µ )/ all flavours (N cos(zen) 0

63 28 ντ Appearance in PINGU Direct measure of Uτ3 2 Energy and zenith angle excess in cascade channel (GeV) E ν livetime: 1 year PINGU preliminary cos(zen) N all flavours -N νe +ν µ )/ all flavours (N PINGU plots currently use same initial Boosted Decision Tree as NMH, but secondary selection for `cascades

64 28 ντ Appearance in PINGU Direct measure of Uτ3 2 Energy and zenith angle excess in cascade channel PINGU plots currently use same initial Boosted Decision Tree as NMH, but secondary selection for `cascades (GeV) E ν Significance to exclude no ν τ appearance (σ) cos(zen) livetime: 1 year PINGU preliminary PINGU true ν τ norm=1 preliminary expected ±1σ ±2σ α=β limit Gaussian approximation Livetime (months) N all flavours -N νe +ν µ )/ all flavours (N

65 Measuring ντ Appearance 29

66 Measuring ντ Appearance Events/year PINGU E ν [1,80] GeV preliminary νµ νe ντ cos(zen) 29

67 Measuring ντ Appearance Events/year PINGU E ν [1,80] GeV preliminary normalization PINGU νµ νe ντ cos(zen) True ν τ 0.5 5σ preliminary expected ±1σ ±2σ measured ν τ norm= Livetime (months) 29

68 30 Conclusions IceCube is opening a new window on neutrino astronomy with 5.7σ observation of astrophysical neutrinos and probing atmospheric charm meson production! Potential with PINGU to quickly resolve the ordering of the neutrino mass hierarchy in addition to enhancing other physics (ντ appearance, non-maximal θ 23, O(1) GeV dark matter, )

69 31 IceCube is opening a new window on neutrino astronomy with 5.7σ observation of astrophysical neutrinos and probing atmospheric charm hadron production Potential with PINGU to quickly resolve the ordering of the neutrino mass hierarchy in addition to enhancing other physics (ν τ appearance, non-maximal θ 23, O(1) GeV dark matter, )

70 31 IceCube is opening a new window on neutrino astronomy with 5.7σ observation of astrophysical neutrinos and probing atmospheric charm hadron production Potential with PINGU to quickly resolve the ordering of the neutrino mass hierarchy in addition to enhancing other physics (ν τ appearance, non-maximal θ 23, O(1) GeV dark matter, )

71 32

72 33 Backup

73 34 Science Portfolio (Partial) Measurements Cosmic Ray Anisotropy - arxiv: Diffuse Neutrino Flux - arxiv: Atmospheric Neutrino Spectrum - arxiv: Neutrino Oscillation - arxiv: Atmospheric Electron Neutrino Flux - arxiv: Searches Supernova 2008D - arxiv: Neutrino Induced Cascades - arxiv: Neutrino Emission Constraints on 2010 Crab Flare - arxiv: Point Sources - arxiv: , Gamma Ray Burst Neutrino Emission - arxiv: Slow Magnetic Monopole - arxiv: Dark Matter - arxiv: , ,

74 35 HESE-III Event Breakdown

75 Potential High Energy Extension (HEX) DecaCube (1/2/3) IceCube DeepCore Spacing 1 (120m): IceCube (1 km 3 ) + 98 strings (1,3 km 3 ) = 2,3 km 3! Spacing 2 (240m): IceCube (1 km 3 ) + 99 strings (5,3 km 3 ) = 6,3 km 3! Spacing 3 (360m): IceCube (1 km 3 ) + 95 strings (11,6 km 3 ) = 12,6 km 3 Chosen geometry not optimum (i.e. for HESE) historically chosen to demonstrate that we do respect boundary conditions *courtesy of C. Wiebusch (RTWH Aachen) 36

76 37 Dark Matter in PINGU Probes lower mass region! Independent test of Spin-Independent results from direct detection experiments