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- Achterberg, A., et al.
(author)
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Detection of atmospheric muon neutrinos with the IceCube 9-string detector
- 2007
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In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998. ; 76:2, s. 027101-
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Journal article (peer-reviewed)abstract
- The IceCube neutrino detector is a cubic kilometer TeV to PeV neutrino detector under construction at the geographic South Pole. The dominant population of neutrinos detected in IceCube is due to meson decay in cosmic-ray air showers. These atmospheric neutrinos are relatively well understood and serve as a calibration and verification tool for the new detector. In 2006, the detector was approximately 10% completed, and we report on data acquired from the detector in this configuration. We observe an atmospheric neutrino signal consistent with expectations, demonstrating that the IceCube detector is capable of identifying neutrino events. In the first 137.4 days of live time, 234 neutrino candidates were selected with an expectation of 211 +/- 76.1(syst)+/- 14.5(stat) events from atmospheric neutrinos.
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2. |
- Achterberg, A., et al.
(author)
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Multiyear search for a diffuse flux of muon neutrinos with AMANDA-II
- 2007
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In: Physical Review D - Particles, Fields, Gravitation and Cosmology. - 1550-7998. ; 76:4, s. 042008-
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Journal article (peer-reviewed)abstract
- A search for TeV-PeV muon neutrinos from unresolved sources was performed on AMANDA-II data collected between 2000 and 2003 with an equivalent live time of 807 days. This diffuse analysis sought to find an extraterrestrial neutrino flux from sources with nonthermal components. The signal is expected to have a harder spectrum than the atmospheric muon and neutrino backgrounds. Since no excess of events was seen in the data over the expected background, an upper limit of E-2 Phi(90%C.L.)< 7.4x10(-8) GeV cm(-2) s(-1) sr(-1) is placed on the diffuse flux of muon neutrinos with a Phi proportional to E-2 spectrum in the energy range 16 TeV to 2.5 PeV. This is currently the most sensitive Phi proportional to E-2 diffuse astrophysical neutrino limit. We also set upper limits for astrophysical and prompt neutrino models, all of which have spectra different from Phi proportional to E-2.
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3. |
- Ackermann, M., et al.
(author)
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Search for ultra-high-energy neutrinos with amanda-II
- 2008
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In: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 675:2, s. 1014-1024
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Journal article (peer-reviewed)abstract
- A search for diffuse neutrinos with energies in excess of 10(5) GeV is conducted with AMANDA-II data recorded between 2000 and 2002. Above 10(7) GeV, the Earth is essentially opaque to neutrinos. This fact, combined with the limited overburden of the AMANDA-II detector ( roughly 1.5 km), concentrates these ultra-high-energy neutrinos at the horizon. The primary background for this analysis is bundles of downgoing, high-energy muons from the interaction of cosmic rays in the atmosphere. No statistically significant excess above the expected background is seen in the data, and an upper limit is set on the diffuse all-flavor neutrino flux of E-2 Phi(90%CL) < 2.7x10(-7) GeV cm(-2) s(-1) sr(-1) valid over the energy range of 2x10(5) to 10(9) GeV. A number of models that predict neutrino fluxes from active galactic nuclei are excluded at the 90% confidence level.
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