Neutrinos in Ice Cube Atmospheric diffuse GZK May
Neutrinos in Ice. Cube Atmospheric “diffuse” GZK May 12, 2009 PS 638 Tom Gaisser 1
Limits on excess of n above atmospheric background May 12, 2009 PS 638 Tom Gaisser 2
Ice. Cube 22 atmospheric n Analysis of D. Chirkin 1. Event selection – 10 -6 signal / Back. 2. Check zenith angle 3. Measure m energy 4. Unfold atmospheric n spectrum May 12, 2009 PS 638 Tom Gaisser 3
IC 22 Atmosnu (cont’d. ) May 12, 2009 PS 638 Tom Gaisser 4
Atmospheric muons (shape only) May 12, 2009 PS 638 Tom Gaisser 5
Unfolding V. Blobel, hep-ex/0208022 v 1 May 12, 2009 PS 638 Tom Gaisser 6
Is there an isotropic (charm) component? May 12, 2009 PS 638 Tom Gaisser 7
GZK neutrino rates in Ice. Cube May 12, 2009 PS 638 Tom Gaisser 8
Detecting neutrinos • Rate – Convolution of: • • • Neutrino flux Absorption in Earth Neutrino cross section Range of muon Size of detector Probability to detect nm-induced muon: May 12, 2009 PS 638 Tom Gaisser 9
Density profile of the Earth May 12, 2009 PS 638 Tom Gaisser 10
Neutrino effective area • Rate: = ∫fn(En)Aeff(En)d. En • Earth absorption – 10 -100 Te. V • cos(q) > -0. 8 • Main effect near vertical – Higher energy n’s absorbed at larger angles May 12, 2009 PS 638 Tom Gaisser 11
Angular acceptance for GZK n from Todor’s lecture of May 5 Which flux was assumed? May 12, 2009 PS 638 Tom Gaisser 12
Model dependence of cosmogenic n N. Busca Pure protons Mixed Cosmic rays Neutrinos May 12, 2009 PS 638 Tom Gaisser 13
Neutrinos: important bi-product in Auger A neutrino can induce a young horizontal shower ! Karl-Heinz Kampert h at µ em 1 h m ν ~30 atm
nt regeneration, horizontal t showers nt + nucleon t + hadrons t decays nt + xxx etc. May 12, 2009 PS 638 Tom Gaisser 15
Ee. V nt detection with Auger et al. D. Gora <~ 1 GZK nt / year in Auger Gct ~ 100 km for Et ~ 2 x 1018 e. V followed by t-decay shower T. Weiler, D. Fargion May 12, 2009 PS 638 Tom Gaisser 16
Auger limit on Earth-skimming nt May 12, 2009 PS 638 Tom Gaisser 17
Km 3 telescopes can also do nt G. Miele --talk describes how to unfold neutrino Cross section May 12, 2009 PS 638 Tom Gaisser 18
Detector was tested in pulsed electron beam at SLAC – Jeff Kowalski May 12, 2009 PS 638 Tom Gaisser 19
May 12, 2009 PS 638 Tom Gaisser 20
May 12, 2009 PS 638 Tom Gaisser 21
Proposed detectors AURA at South Pole digitize signal at antenna cluster --Hagar Landsman ARIANNA Steve Barwick May 12, 2009 PS 638 Tom Gaisser 22
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