Neutrinos and Beyond New Windows on Nature (2003) / Chapter Skim
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3 Science Potential of Icecube
3 Science Potential of Icecube
Pages 22-31
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From page 22... ...
· How do supermassive black holes produce very high energy gamma rays? INTRODUCTION IceCube is an exploratory experiment in that it will search for astrophysical neutrinos in the very high energy range with much greater sensitivity than previ22
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From page 23... ...
Possible sources include gamma-ray bursts, which are powerful explosions that release in seconds the same energy as a typical galaxy emits in years; active galaxies and quasars, which can be more than 1,000 times more luminous than normal galaxies and are believed to be powered by supermassive black holes at their centers; and neutron stars, which are ultracompact stellar remnants that have collapsed to densities comparable to those inside atomic nuclei. In addition, the possibility exists for new and unexpected types of sources, both astrophysical and exotic, at these energies.
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From page 24... ...
The experiments planned for the South Pole and for the Mediterranean are largely complementary in nature, in terms of both their observational targets and their capabilities. By detecting upward-going muons, IceCube is sensitive to astrophysical sources in the Northern Celestial Hemisphere, whereas a Mediterranean Sea experiment would study Southern Celestial Hemisphere sources.
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From page 25... ...
A variety of astrophysical measurements using photons or cosmic rays support the idea that there are sources of high-energy neutrinos, but their exact flux levels are uncertain. Gamma-ray telescopes on Earth and in space have shown that both galactic sources, such as pulsars and supernova remnants (produced when massive stars explode)
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From page 26... ...
(c) Lowering one of the strings of light sensors; the glass capsule encases the photomultiplier tube.
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From page 27... ...
(b) Image of Earth courtesy of the Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California; image of NGC 4261 courtesy of Greg Taylor/NRAO; image of Hydra A courtesy of NASA/Jeffe, Ford, Ferrarese, Van Den Bosch, O'Connell, and NRAO.
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From page 28... ...
Current models of GRBs involve the dissipation of the kinetic energy of a relativistically expanding fireball, caused by some explosive event, possibly the collapse of a massive star or the coalescence of two compact objects. The shocks resulting from this dissipation can accelerate particles to very high energies (gamma rays up to 10~° eV energies have been detected from GRBs)
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From page 29... ...
The exact level of this atmospheric neutrino background depends on the unknown forward production of neutrinos from charm quark decays. On the one hand, if this production channel is very efficient, the flux of atmospheric neutrinos as well as the flux of astrophysical neutrino point sources will increase accordingly.
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From page 30... ...
Among the early universe relics that IceCube can study are the likeliest form of dark-matter particles, called neutralinos, whose collective gravitational force appears to dominate that of the ordinary visible matter in galaxles. NeutraTinos may be indirectly detected by high-energy neutrino telescopes (e.g., IceCube)
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From page 31... ...
Finally, the detection of high-energy neutrinos from a known astrophysical source can be used to test the assumption of special relativity that photons and neutrinos have the same limiting speed, as well as the weak equivalence principle, according to which photons and neutrinos should suffer the same time delay as they pass through the gravitational potential of galaxies. Other departures from the Standard Model predictions, such as new physics at scales of beyond 10~2 eV the highest energies currently available from terrestrial accelerators might also be inferred by studying the neutrino cross section on hadrons at energies well above 10~2 eV.
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