Search Results: Neutrino astronomy

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Figure 1.The cosmic-neutrino spectrum. Sources are the big bang (C?B), which produced a relic background of neutrinos; the Sun (pp and 8B); a future galactic supernova assumed to explode at a distance of 10 kpc (SN); the supernova SN1987A; the total flux produced by past supernovae over cosmic time (relic); atmospheric neutrinos; active galactic nuclei (AGN); gamma-ray bursts (GRB); and GZK neutrinos, produced by extragalactic cosmic rays interacting with microwave photons. The data points are from detectors at the Frejus underground laboratory (black squares) and from AMANDA (color circles). (Copyright © J. K. Becker; adapted from J. K. Becker, High-energy neutrinos in the context of multimessenger astrophysics, Phys. Rep., 458:173–246, 2008)

From Encyclopedia article 'Neutrino astronomy'

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Figure 2.Conceptual design of a large neutrino detector. A neutrino (?), selected by the fact that it traveled through the Earth, enters from the lower right and interacts with a nucleus in the ice, producing a muon (µ) that is detected by the wake of Cerenkov photons (Cerenkov cone) that it leaves inside the detector. (Courtesy ofIceCube Research Center)

From Encyclopedia article 'Neutrino astronomy'

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Figure 3.Using declination and right ascension as coordinates, the map shows the arrival directions of 14,121 neutrinos in the Northern Hemisphere and 22,779 high-energy down-going muons in the Southern Hemisphere collected when IceCube operated with 40 strings for one year. The line shows the outline of the galactic plane. The map is searched for clustering of events and for events with such high energy that they are unlikely to be atmospheric in origin. Their neutrino energies range from 100 GeV to several hundred TeV. The “hottest spot” in the map has an excess of 7 events, an excursion from the atmospheric background with a probability of 10-4.4. After taking into account trial factors, the probability of getting a spot this hot somewhere in the sky is not significant. (J. Dumm et al. for the IceCube Collaboration, Proceedings of the 31st International Cosmic Ray Conference, Lódz, Poland, July 8–15, 2009)

From Encyclopedia article 'Neutrino astronomy'