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venice. XIII. francis halzen University of Wisconsin http://icecube.wisc.edu. it’s the technology ! cosmic accelerators neutrinos associated with Galactic cosmic rays extragalactic cosmic rays status of neutrino astronomy to lower energies to higher energies conclusions. menu.
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venice XIII francis halzen University of Wisconsin http://icecube.wisc.edu
it’s the technology ! cosmic accelerators neutrinos associated with Galactic cosmic rays extragalactic cosmic rays status of neutrino astronomy to lower energies to higher energies conclusions menu
M. Markov 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.
shielded and optically • transparent medium m n • lattice of photomultipliers
F. Reines K. Greissen Requires Kilometer-Scale Neutrino Detectors
Lake Baikal ice as a natural deployment platform neutrinos! Camp
Antares Nestor March 17, 2003 2 strings connected 2400 m deep start 2006 March 29, 2003 1 of 12 floors deployed 4000 m deep mediterranean detectors Nemo towards KM3NeT
2006-2007: 13 Strings 2007-2008: 18 Strings 2004-2005 : 1 String 2008-2009: 18+1 Strings 2005-2006: 8 Strings 1450 m 2450 m since jan 09 59 out of 86
IceCube Neutrino Observatory South Pole Drilling Seasons 1996/2000 Seasons -AMANDA2008/2009 Season - 18 Strings 2005/2006 Season - First String 2009/2010 Season - 16 to 19 Strings 2006/2007 Season - 8 Strings 2010/2011 Season - 18 to 20 Strings 2007/2008 Season - 13 Strings 2011/2012 Season - Remaining 6 to 15 Strings • Avg. time to deep drill hole 41hrs • Avg. hole depth 2452 m • Avg. drilling rate 1.7 m/min • Avg. fuel per hole 5 ,520 gal • Drill thermal power output 4.7 MW • Avg. string deployment time 8 hrs
IceCube then and now simple 8-fold majority trigger neutrino area predicted performance level 2 (red) Astroparticle Physics 20, 507 (2004) deep core
back to neutrinos…50 years later • we have detected neutrinos, in ice and in water • we know how to build kilometer-scale detectors • an impressive achievement
separate neutrinos (filtered by the Earth) from down- going cosmic ray muons at a level of much less than one per million the challenge: p atm p
within trigger time window down down down up
IceCube background: downgoing cosmic ray muons ~ 2000 per second signal: upgoing muons initiated by neutrinos ~ 10 per hour
ANTARES EVENTDISPLAY EXAMPLE OF NEUTRINO CANDIDATE Neutrino Astronomy ANTARES Height of hit OM Analysis of the5Line data 26 Time of hit Example of a reconstructed up-going muon (i.e. a neutrino candidate) detected in 5/12 detector lines.
Dornic, Moriond 2009 ANTARES
is the background more interesting ? the muon sky is not isotropic Tibet array: northern hemisphere
the 100 TeV cosmic ray sky is not isotropicIceCube4x109 muons of 14TeV
Milagro cosmic ray sky between a few and 30 degrees 3 degree point source
50 years later • we have detected neutrinos, in ice and in water • we know how to build kilometer-scale detectors • an impressive achievement, but after 10,000 n’s • we have still not detected a cosmic neutrino after early 1990’s days of irrational exhuberance the predictions have been stable and the goals defined
it’s the technology ! cosmic accelerators neutrinos associated with Galactic cosmic rays extragalactic cosmic rays status of neutrino astronomy to lower energies to higher energies conclusions menu
nature’s accelerators ? protons > 108 TeV photons > 102 TeV neutrinos > 102 TeV
shock acceleration (solar flare) coronal mass ejection 10 GeV particles
cassiopeia A supernova remnant in X-rays shock fronts acceleration when particles cross high B-fields
collapse of massive star produces a gamma ray burst spinning black hole g’s and protons (cosmic rays) coexist produce n’s
active galaxyparticle flowspowered by thegravity ofsupermassiveblack hole
Neutrino Beams: Heaven & Earth n and g beams : heaven and earth NEUTRINO BEAMS: HEAVEN & EARTH Black Hole Radiation Enveloping Black Hole p + g n + p+ ~ cosmic ray + neutrino p + p0 ~ cosmic ray + gamma
it’s the technology ! cosmic accelerators neutrinos associated with cosmic rays Galactic cosmic rays extragalactic cosmic rays status of neutrino astronomy to lower energies to higher energies conclusions menu
galactic and extragalactic cosmic rays galactic extragalactic
galactic cosmic rays 10-41 erg/cm3 energy (eV) galactic cosmic rays 10-12 erg/cm3 / / / / / / / / / / / / / / / / / CMB Radio Visible extragalactic cosmic rays 10-19 erg/cm3 flux 410 photons of 2.7 K or 10-12 erg/cm3 GeV g-rays
energy in extra-galactic cosmic raysis~ 3x10-19 erg/cm3 3x1044 erg/s per active galaxy 2x1052 erg per gamma ray burst energy in cosmic rays ~ photons ~ neutrinos
neutrinos associated with extragalactic cosmic rays AMANDA IceCube
active galaxy Centaurus A M87 Fornax A … supermassive supermassive black hole black hole • accretion disk jet •
neutrino astronomy kilometer scale detectors have the capability of detecting astrophysical neutrinos from cosmic sources with an energy density in neutrinos comparable to their energy density in the observed cosmic rays • this is the case for gamma ray bursts if they are the • sources of the extragalactic cosmic rays • for active galaxies it is also the case but the uncertain- • ties are very large because of the variability of the • sources • it is definitely the case for galactic supernova remnants