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We perform a realistic evaluation of the potential of IceCube, a kilometer-scale neutrino detector under construction at the South Pole, to detect neutrinos in the direction of the potential accelerators of the Galactic cosmic rays. We take fully account of the fact that the measurement of the energy of the secondary muons at the detector can be used to further discriminate between the signal and the background of atmospheric neutrinos. A PeVatron is defined as the accelerator of cosmic rays with energies of several PeV, the knee in the spectrum; it has a hard energy spectrum and produces secondary photons of hundreds of GeV on the interstellar medium. Assuming that the Milagro sources are PeVatrons, an IceCube analysis combining the information from the different sources can reveal them as such at the 3σ level in one year and at the 5σ level in three years. We discuss the dependence of these expectations on the considerable ambiguities associated with the source spectra. 相似文献
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D. Gough 《Astrophysics and Space Science》2003,285(2):341-351
In 1970 Fred Hoyle encouraged a study of solar neutrino production which led to along-term investigation of the influence
of what have become known as `non-standard' processes (i.e. processes that are not accounted for in the relatively naively
constructed so-called `standard' theoretical solar models). The outcome is a very much sounder understanding of the structure
and dynamics of the Sun, which has yielded a knowledge of conditions in the energy-generating core so precise that one can
set quite tight reliable constraints on neutrino-producing nuclear reactions, and thereby provide an important contribution
to the study of neutrino transitions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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We investigate the possibility to use the neutrinos coming from a future galactic supernova explosion to perform neutrino oscillation tomography of the Earth’s core. We propose to use existing or planned detectors, resulting in an additional payoff. Provided that all of the discussed uncertainties can be reduced as expected, we find that the average matter densities of the Earth’s inner and outer cores could be measured with a precision competitive with geophysics. However, since seismic waves are more sensitive to matter density jumps than average matter densities, neutrino physics would give partly complementary information. 相似文献
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Young, rapidly rotating neutron stars could accelerate ions from their surfaces to energies of ∼1 PeV. If protons reach such energies, they will produce pions (with low probability) through resonant scattering with X-rays from the stellar surface. The pions subsequently decay to produce muon neutrinos. Here, we calculate the energy spectrum of muon neutrinos, and estimate the event rates at Earth. The spectrum consists of a sharp rise at ∼50 TeV, corresponding to the onset of the resonance, above which the flux drops with neutrino energy as ε−2 ν up to an upper energy cut-off that is determined by either kinematics or the maximum energy to which protons are accelerated. We estimate event rates as high as 10–100 km−2 yr−1 from some candidates, a flux that would be easily detected by IceCube. Lack of detection would allow constraints on the energetics of the poorly understood pulsar magnetosphere. 相似文献