Gravitation, Cosmology, and Cosmic-Ray Physics (1986) / Chapter Skim
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17. Opportunities
17. Opportunities
Pages 143-156
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From page 143... ...
Ground-based instruments infer energy spectra and composition of cosmic rays above about 10'4 eV by measurements of the showers of secondary particles produced by interactions of the primary cosmic rays in the atmosphere. In addition, for particles that penetrate the atmosphere, such as neutrinos and perhaps magnetic monopoles, certain ground-based instruments may detect the primary particle.
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From page 144... ...
There are also important observations that can be made with instruments already built or under construction, attached to the Space Shuttle, the Space Station, or the Long Duration Exposure Facility. In addition there are also a few key experiments, using space-proven solid-state detector technology, that require exposure outside the magnetosphere and can be placed there with Shuttle launch and subsequent upper-stage boost.
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From page 145... ...
With developments over the past decade in superconducting magnet technology in a wide variety of ground-based applications, and the developments of cryogenic applications in space, such a device appears to be quite feasible for installation on the Space Station in the early 1990s. SOLAR-FLARE ISOTOPES We have only limited direct knowledge of the Sun's elemental composition and almost no direct knowledge of its isotopic composition.
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From page 146... ...
If the fraction of reprocess material were appreciably greater than 10 percent, one could even estimate the time of the reprocess addition from the relative abundances of these elements. It appears that this next major step in the study of ultraheavy nuclei can be achieved relatively inexpensively using newly developed plastic track detectors on a flight of the Long Duration Exposure Facility (LDEF)
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From page 147... ...
Positrons, Antiprotons, Deuterium, and 3He Several significant questions about the galactic containment of cosmic rays require the observation of the secondary cosmic rays generated by interstellar collisions of the most abundant cosmic-ray species protons and alpha particles. These observations are best performed with counter telescopes featuring magnetic spectrometers with superconducting magnets flown on the Space Station.
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From page 148... ...
A much more sensitive search, at the level of 10-8, over the full range of abundant elements from helium through iron, would be possible with a superconducting magnetic spectrometer on the Space Station. Nucleus-Nucleus Interactions The study of nucleus-nucleus interactions at high energies has become of great interest in the past few years because of elementaryparticle theories that predict new states of matter that can be created only in such collisions, in particular the quark-gluon plasma.
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From page 149... ...
As these probes penetrate uncharted regions of the solar system, it is important to preserve monitors of the magnitude of the solar modulation including near-Earth spacecraft and ground-level neutron monitors. Neutron monitors provide a precise continuous monitor of the cosmic-ray flux at the Earth by measuring secondary nucleons produced in the atmosphere by nuclear interactions of primary cosmic-ray nuclei.
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From page 150... ...
program directed toward the study of extensive air showers produced by primary cosmic rays of over 10'7 eV is the Fly's Eye installation in Utah, described earlier. This detector has been expanded by increasing the number of mirrors and phototubes at the second, newer site by a factor of 3.
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From page 151... ...
Thus, it has been tempting to consider developing a neutrino astronomy to seek signals from a variety of astronomical sources. It has been proposed to instrument a large volume of seawater with photomultipliers to seek Cerenkov signals from such neutrino interactions.
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From page 152... ...
NEUTRINOS MAGNETIC MONOPOLES GAMMA RAYS PROTONS AND NUCLEI -AS SEEN BY MUONS -AS SEEN BY AIR SHOWERS '//////\\\\\\\' /////// / / / / \\\\\\\\\ HOMESTAKE I/~\B DUMAND FLY'S EYE //i/ / //// ///// ////////////////// SUPERCONDUCTING COIL DETECTORS SCINTILLATION DETECTORS A///////////\\\\\\ CERENKOV AIR SHOWER DETECTORS ARRAYS '////~0~1111 1 1 1 1 1 PROTON HOMESTAKE DUMAND DECAY DETECTORS SURFACE FLY'S EYE ARRAY loin lol2 ic14 iol6 EN ERGY ( ELECTRON VOLTS ) FIGURE 17.1 The range of energy sensitivity for different particle types of the present and proposed ground-based detectors discussed in this section.
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From page 153... ...
They are large underground detectors sensitive to energetic cosmic-ray muons and to neutrino interactions. The largest nucleon decay detectors have measured for the first time the flux of cosmic-ray neutrinos by directly observing their interactions inside the detector volume in significant numbers.
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From page 154... ...
As the primary cosmic-ray energies explored are within the range of the current generation of pp colliders, these data are of interest principally in the context of the properties of nucleus-nucleus collisions. Solar Neutrinos The importance of the solar neutrino experiment has been correctly emphasized in the report of the Astronomy Survey Committee (Astronomy and Astrophysic s for the 1 980's, Volume 1, National Academy Press, Washington, D.C., 19821.
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From page 155... ...
Understanding the nearest star depends on modeling of the nuclear reaction cycle in the Sun and other solar calculations, which underlie, for example, interpretations of solar neutrino experiments. The processes by which cosmic rays are accelerated to exceedingly high, suprathermal energies are intrinsically interesting, and significant theoretical progress is being made in understanding them.
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From page 156... ...
156 COSMIC RA YS the background for underground experiments, such as the search for nucleon decay, and to determine the level at which neutrino astronomy may be possible. Another subject of great current interest is the calculation of flux limits on magnetic monopoles from galactic magnetic fields and neutron star brightness.
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