1. Ultra - High Energy Neutrino Astronomy Ultra - High Energy Neutrino Astronomy DmitrySemikoz UCLA, Los Angeles in collaboration with F.Aharonian, A.Dighe, O.Kalashev, M.Kachelriess, V.Kuzmin, A.Neronov, G.Raffelt, G.Sigl, M.Tortola and R.Tomas

2. Fermilab February 9, 2004 Overview: Introduction: high energy neutrinos Experimental detection of high energy neutrinos:  Under/ground/water/ice  Horizontal air showers  Radio detection  Acoustic signals from neutrinos Neutrinos from UHECR protons Neutrinos from AGN

3. Fermilab February 9, 2004 Most probable neutrino sources Neutrinos from Galactic SN Neutrinos in exotic UHECR models Conclusion

4. Fermilab February 9, 2004 INTRODUCTION

5. Fermilab February 9, 2004 Extragalactic neutrino flux? Sanduleak –69 202 Large Magellanic Cloud Distance 50 kpc (160.000 light years) Tarantula Nebula Supernova 1987A 23 February 1987 Georg Raffelt, Max-Planck-Institut für Physik (München)

6. Fermilab February 9, 2004 Neutrino Signal from SN 1987A Kamiokande (Japan) Kamiokande (Japan) Water Cherenkov detector Water Cherenkov detector Clock uncertainty  1 min Clock uncertainty  1 min Kamiokande (Japan) Kamiokande (Japan) Water Cherenkov detector Water Cherenkov detector Clock uncertainty  1 min Clock uncertainty  1 min Irvine-Michigan-Brookhaven Irvine-Michigan-Brookhaven (USA) (USA) Water Cherenkov detector Water Cherenkov detector Clock uncertainty  50 ms Clock uncertainty  50 ms Irvine-Michigan-Brookhaven Irvine-Michigan-Brookhaven (USA) (USA) Water Cherenkov detector Water Cherenkov detector Clock uncertainty  50 ms Clock uncertainty  50 ms Baksan Scintillator Telescope Baksan Scintillator Telescope (Soviet Union) (Soviet Union) Clock uncertainty +2/-54 s Clock uncertainty +2/-54 s Baksan Scintillator Telescope Baksan Scintillator Telescope (Soviet Union) (Soviet Union) Clock uncertainty +2/-54 s Clock uncertainty +2/-54 s Within clock uncertainties, Within clock uncertainties, signals are contemporaneous signals are contemporaneous Within clock uncertainties, Within clock uncertainties, signals are contemporaneous signals are contemporaneous

7. Fermilab February 9, 2004 Atmospheric n's in AMANDA-II  neural network energy reconstruction  regularized unfolding  spectrum up to 100 TeV  compatible with Frejus data In future, spectrum will be used to study excess due to cosmic ‘s PRELIMINARY 1 TeV

8. Fermilab February 9, 2004 Why UHE neutrinos can exist? Protons are attractive candidates to be accelerated in astrophysical objects up to highest energies E~10 20 eV. Neutrinos can be produced by protons in P+P  pions or P+  pions reactions inside of astrophysical objects or in intergalactic space. Neutrinos can be produced directly in decays of heavy particles. Same particles can be responsible for UHECR events above GZK cutoff.

9. Fermilab February 9, 2004 Pion production p n Conclusion: proton, photon and neutrino fluxes are connected in well-defined way. If we know one of them we can predict other ones:

10. Fermilab February 9, 2004 High energy neutrino experiments

11. Fermilab February 9, 2004 Neutrino – nucleon cross section Proton density n p ~ 10 24 /cm 3 Distance R~10 4 km Cross section  N =1/(Rn p )~10 -33 cm 2 This happens at energy E~10 15 eV. ~E 0.4

12. Fermilab February 9, 2004 Experimental detection of E<10 17 eV neutrinos Neutrinos coming from above are secondary from cosmic rays Neutrino coming from below are mixture of atmospheric neutrinos and HE neutrinos from space Earth is not transparent for neutrinos E>10 15 eV Experiments: MACRO, Baikal, AMANDA

13. Fermilab February 9, 2004 Experimental detection of UHE (E>10 17 eV) neutrinos Neutrinos are not primary UHECR Horizontal or up-going air showers – easy way to detect neutrinos Experiments: Fly’s Eye, AGASA, HiRes

14. Fermilab February 9, 2004 Radio detection

15. Fermilab February 9, 2004 e + n  p + e - e - ... cascade  relativist. pancake ~ 1cm thick,  ~10cm  each particle emits Cherenkov radiation  C signal is resultant of overlapping Cherenkov cones  for >> 10 cm (radio) coherence  C-signal ~ E 2 nsec negative charge is sweeped into developing shower, which acquires a negative net charge Q net ~ 0.25 E cascade (GeV). Threshold > 10 16 eV Experiments: GLUE, RICE, FORTE

16. Fermilab February 9, 2004 Acoustic detection

17. Fermilab February 9, 2004 d R Particle cascade  ionization  heat  pressure wave P t ss Attenuation length of sea water at 15-30 kHz: a few km (light: a few tens of meters) → given a large initial signal, huge detection volumes can be achieved. Threshold > 10 16 eV Maximum of emission at ~ 20 kHz

18. Fermilab February 9, 2004 Renewed efforts along acoustic method for GZK neutrino detection Greece: SADCO Mediterannean, NESTOR site, 3 strings with hydrophones Russia: AGAM antennas near Kamchatka: existing sonar array for submarine detection Russia: MG-10M antennas: withdrawn sonar array for submarine detection AUTEC: US Navy array in Atlantic: existing sonar array for submarine detection Antares: R&D for acoustic detection IceCube: R&D for acoustic detection

19. Fermilab February 9, 2004 Present limits on neutrino flux

20. Fermilab February 9, 2004 MACRO

21. Fermilab February 9, 2004 FORTE

22. Fermilab February 9, 2004 4-string stage (1996) First underwater telescope First neutrinos underwater

23. Fermilab February 9, 2004 AMANDA-II depth AMANDA Super-K DUMAND Amanda-II: 677 PMTs at 19 strings (1996-2000)

24. Fermilab February 9, 2004 AGASA AGASA covers an area of about 100 km 2 and consists of 111 detectors on the ground (surface detectors) and 27 detectors under absorbers (muon detectors). Each surface detector is placed with a nearest-neighbor separation of about 1 km.

25. Fermilab February 9, 2004 High Resolution Fly’s Eye: HiRes HiRes 1 and HiRes 2 sit on two small mountains in western Utah, with a separation of 13 km. HiRes 1 has 21 three meter diameter mirrors which are arranged to view the sky between elevations of 3 and 16 degrees over the full azimuth range; HiRes 2 has 42 mirrors which image the sky between elevations of 3 and 30 degrees over 360 degrees of azimuth. At the focus of each mirror is a camera composed of 256 40-mm diameter hexagonal photomultiplier tubes, each tube viewing a 1 degree diameter section of the sky.

26. Fermilab February 9, 2004 GLUE G oldstone L unar U ltra-high Energy Neutrino E xperiment  E 2 ·dN/dE < 10 5 eV·cm -2 ·s -1 ·sr -1 Lunar Radio Emissions from Inter- actions of and CR with > 10 19 eV 1 nsec moon Earth Gorham et al. (1999), 30 hr NASA Goldstone 70 m antenna + DSS 34 m antenna at 10 20 eV Effective target volume ~ antenna beam (0.3°)  10 m layer  10 5 km 3

27. Fermilab February 9, 2004 RICE R adio I ce C herenkov E xperiment firn layer (to 120 m depth) UHE NEUTRINO     DIRECTION 300 METER DEPTH E 2 · dN/dE < 10 -4 GeV · cm -2 · s -1 · sr -1 20 receivers + transmitters at 10 17 eV

28. Fermilab February 9, 2004 Future limits on neutrino flux

29. Fermilab February 9, 2004 Mediterranean Projects 4100m 2400m 3400m ANTARES NEMO NESTOR

30. Fermilab February 9, 2004 NEMO 1999 - 2001 Site selection and R&D 2002 - 2004 Prototyping at Catania Test Site 2005 - ? Construction of km 3 Detector ANTARES 1996 - 2000 R&D, Site Evaluation 2000 Demonstrator line 2001 Start Construction September 2002 Deploy prototype line December 2004 10 (14?) line detector complete 2005 - ? Construction of km 3 Detector NESTOR 1991 - 2000 R & D, Site Evaluation Summer 2002 Deployment 2 floors Winter 2003 Recovery & re-deployment with 4 floors Autumn 2003 Full Tower deployment 2004 Add 3 DUMAND strings around tower 2005 - ? Deployment of 7 NESTOR towers

31. Fermilab February 9, 2004 Baikal km 3 project: Gigaton Volume Detector GVD

32. Fermilab February 9, 2004 IceCube 1400 m 2400 m AMANDA South Pole IceTop - 80 Strings - 4800 PMT - Instrumented volume: 1 km 3 - Installation: 2004-2010 ~ 80.000 atm. per year

33. Fermilab February 9, 2004 Pierre Auger observatory

34. Fermilab February 9, 2004 Telescope Array

35. Fermilab February 9, 2004 MOUNT

36. Fermilab February 9, 2004 OWL/EUSO

37. Fermilab February 9, 2004 ANITA An tarctic I mpulsive T ransient A rray Flight in 2006

38. Fermilab February 9, 2004 Natural Salt Domes Potential PeV-EeV Neutrino Detectors SalSA Sal t Dome S hower A rray

39. Fermilab February 9, 2004 Renewed efforts along acoustic method for GZK neutrino detection Greece: SADCO Mediterannean, NESTOR site, 3 strings with hydrophones Russia: AGAM antennas near Kamchatka: existing sonar array for submarine detection Russia: MG-10M antennas: withdrawn sonar array for submarine detection AUTEC: US Navy array in Atlantic: existing sonar array for submarine detection Antares: R&D for acoustic detection IceCube: R&D for acoustic detection

40. Fermilab February 9, 2004 RICEAGASA Amanda, Baikal 2002 2007 AUGER  Anita AABN 2012 km 3 EUSO, OWL Auger Salsa GLUE 2004 RICE Amanda II

41. Fermilab February 9, 2004 Neutrinos from UHECR protons

42. Fermilab February 9, 2004 Why neutrinos from UHE protons? All experiments agree (up to factor 2) on UHECR flux below cutoff. All experiments see events above cutoff! Majority of the air-showers are hadronic-like Simplest solution for energies 5x10 18 eV < E < 5x10 19 eV: protons from uniformly distributed sources like AGNs.

43. Fermilab February 9, 2004 Active galactic nuclei can accelerate heavy nuclei/protons

44. Fermilab February 9, 2004

45. Photo-pion production p n

46. Fermilab February 9, 2004 Parameters which define diffuse neutrino flux Proton spectrum from one source: Distribution of sources: Cosmological parameters:

47. Fermilab February 9, 2004 Theoretical predictions of neutrino fluxes WB bound: 1/E 2 protons; distribution of sources – AGN; analytical calculation of one point near 10 19 eV. MPR bound: 1/E protons; distribution of sources – AGN; numerical calculation for dependence on E max The  ray bound: EGRET

48. Fermilab February 9, 2004 The high energy gamma ray detector on the Compton Gamma Ray Observatory (20 MeV - ~20 GeV) EGRET: diffuse gamma-ray flux

49. Fermilab February 9, 2004 Detection of neutrino fluxes: today

50. Fermilab February 9, 2004 Future detection of neutrinos from UHECR protons AGN,1/E Old sources 1/E^2 / EUSO

51. Fermilab February 9, 2004 Neutrinos from Active galactic nuclei

52. Fermilab February 9, 2004 Active Galactic Nuclei (AGN) Active galaxies produce vast amounts of energy from a very compact central volume. Prevailing idea: powered by accretion onto super-massive black holes (10 6 - 10 10 solar masses). Different phenomenology primarily due to the orientation with respect to us. Models include energetic (multi-TeV), highly-collimated, relativistic particle jets. High energy  -rays emitted within a few degrees of jet axis. Mechanisms are speculative;  -rays offer a direct probe.

53. Fermilab February 9, 2004 Neutrinos from AGN core / EUSO

54. Fermilab February 9, 2004 Photon background in core Energy scale E  = 0.1 – 10 eV Time variability  few days or R = 10 16 cm Model: hot thermal radiation. T=1 eV T=10 eV

55. Fermilab February 9, 2004 Photo-pion production p n

56. Fermilab February 9, 2004 Neutrino spectrum for various proton spectra and backgrounds 1/E 1/E 2 T=10 eV 1/E 2 T=1 eV E~10 18 eV Atm. flux

57. Fermilab February 9, 2004 Most probable neutrino sources

58. Fermilab February 9, 2004 Optics: SDSS. Most powerful objects are AGNs 500 sq deg of the sky, 14 million objects, spectra for 50,000 galaxies and 5,000 quasars. Distance record-holder >13,000 quasars (26 of the 30 most distant known)

59. Fermilab February 9, 2004 Low energy radiation from AGN is collimated Typical gamma-factor is  Radiation is collimated in 1/  angle ~ 5 o in forward direction.

60. Fermilab February 9, 2004 EGRET 3 rd Catalog: 271 sources Most of identified MeV-GeV sources are blazars

61. Fermilab February 9, 2004 Which sources ? Blazars (angle – energy correlation)

62. Fermilab February 9, 2004 High energy photons from pion decay cascade down in GeV region

63. Fermilab February 9, 2004 EGRET 3 rd Catalog: 271 sources Only 22 sources from 66 are GeV - loud

64. Fermilab February 9, 2004 Which sources ? Blazars (angle – energy correlation) Blazars should be GeV loud (conservative model)

65. Fermilab February 9, 2004 Which sources ? Blazars (angle – energy correlation) Blazars should be GeV loud (conservative model) ‘Optical depth’ for protons should be large:  p  n  R 

66. Fermilab February 9, 2004 Bound on blazars which can be a neutrino sources

67. Fermilab February 9, 2004 TeV blazars does not obey last condition Indeed, in order TeV blazars be a neutrino sources:   p  n  R     n  R   p  = 6x10 -28 cm 2 while   = 6.65 x 10 -25 cm 2 CONTRADICTION!!!

68. Fermilab February 9, 2004 Which sources ? Blazars (angle – energy correlation) Blazars should be GeV loud (conservative model) Optical depth for protons should be large:  p  n  R  No 100 - kpc scale jet detected (model-dependent)

69. Fermilab February 9, 2004 Neutrino production in AGN

70. Fermilab February 9, 2004 Collimation of neutrino flux in compare to GeV flux

71. Fermilab February 9, 2004 Neutrinos from Galactic Supernova

72. Fermilab February 9, 2004 Prompt neutrino signal in 1-50 MeV energies. 1-10 sec after SN burst/Strong signal in each optical module / SN 1987A signal Prompt neutrino signal in 1-50 MeV energies. 1-10 sec after SN burst/Strong signal in each optical module / SN 1987A signal 50-200 events with E> 1TeV in 10-12 hours after burst. Shock front reached surface and became colisionless. Duration t ~ 1 hour / Waxman & Loeb 2001 Duration t ~ 1 hour / Waxman & Loeb 2001 50-200 events with E> 1TeV in 10-12 hours after burst. Shock front reached surface and became colisionless. Duration t ~ 1 hour / Waxman & Loeb 2001 Duration t ~ 1 hour / Waxman & Loeb 2001 SN shock interact with pre-SN wind and interstelar medium. 1000-10000 events with E>1 TeV in km^3 detector From 10 days till 1 year /Berezinsky & Ptuskin 1989 SN shock interact with pre-SN wind and interstelar medium. 1000-10000 events with E>1 TeV in km^3 detector From 10 days till 1 year /Berezinsky & Ptuskin 1989 Possible neutrino signals from Galactic SN in km^3 detector

73. Fermilab February 9, 2004 Supernova Monitor Amanda-II Amanda-B10 IceCube 0 5 10 sec Count rates B10: 60% of Galaxy A-II: 95% of Galaxy IceCube: up to LMC

74. Fermilab February 9, 2004 Pointing to Galactic SN AMANDA II will see 5-20 events with E> 1TeV. For angular resolution 2 o of each event. Pointing to SN direction is possible with resolution ~0.5 o For ANTARES pointing is up to 0.1 o. Compare to SuperKamiokande 8 o now and 3.5 o with gadolinium. HyperKamiokande ~0.6 o

75. Fermilab February 9, 2004 Detection of Galactic SN from wrong side by km^3 detector Atmospheric muons 5*10 10 /year or 300/hour/(1 o ) 2 Signal 200 events, besides energy cut 1 TeV. Angular resolution 0.8 o for each event or less then 0.1 o for SN signal !!! (A.Digle, M.Kachelriess, G.Raffelt, D.S. and R.Tomas, hep-ph/0307050)

76. Fermilab February 9, 2004 Neutrinos from exotic UHECR models

77. Fermilab February 9, 2004 Z-burst mechanism (T.Weiler, 1982) Resonance energy E = 4 10 21 (1 eV/m ) eV Works only if m   eV Mean free path of neutrino is L = 150 000 Mpc >> L univ

78. Fermilab February 9, 2004 Cross sections for neutrino interactions with relict background and 

79. Fermilab February 9, 2004 Pure neutrino sources

80. Fermilab February 9, 2004 Sources of both  and Kalashev, Kuzmin, D.S. and Sigl, hep-ph/0112351

81. Fermilab February 9, 2004 Gelmini-Kusenko model: X->

82. Fermilab February 9, 2004 FORTE and WMAP practically exclude Z-burst model D.S. and G.Sigl, hep-ph/0309328

83. Fermilab February 9, 2004 Top-down models

84. Fermilab February 9, 2004 New hadrons (Kachelriess, D.S. and Tortola, hep-ph/0302161)

85. Fermilab February 9, 2004 Diffuse neutrino flux Flux is unavoidably high due to Shape depends on distribution of background photons and on proton spectrum

86. Fermilab February 9, 2004 Conclusions Sensitivity of the neutrino telescopes will be increased in 10 2-3 times during next 10 years. Now they just on the border of theoretically interesting region. Secondary neutrino flux from UHECR protons can be detected by future UHECR experiments. Neutrino flux from AGN’s can be detected by under-water/ice neutrino telescopes. GeV-loud blazars with high optical depth for protons are good candidates for neutrino sources. Galactic SN can be detected with neutrinos at low and high energies. Some of exotic UHECR models will be ruled out or confirmed in near future by neutrino data.

87. Fermilab February 9, 2004 References: Diffuse neutrino flux. O.Kalashev, V.Kuzmin, D.S. and G.Sigl, hep-ph/0205050; D.S. and G.Sigl, hep-ph/0309328 Extragalactic neutrino sources. A.Neronov & D.S., hep- ph/0208248 AGN jet model. A.Neronov, D.S., F.Aharonian and O.Kalashev, astro-ph/0201410 Z-burst model. O.Kalashev, V.Kuzmin, D.S. and G.Sigl, hep-ph/0112351 New hadrons as UHECR. M.Kachelriess, D.S. and M.Tortola, hep-ph/0302161 SN pointing with low and high energy neutrinos. R.Tomas, D.S., G.Raffelt, M.Kachelriess and A.Dighe, hep- ph/0307050