Charge composition and energy spectra of cosmic-ray nuclei at energies above 5 GeV per nucleon

Journal Article · Mon Nov 14 23:00:00 EST 1977 · Astrophys. J.; (United States)

DOI:https://doi.org/10.1086/155680· OSTI ID:5236449

Caldwell, J H

A scintillation-Cerenkov counter telescope, with three gas Cerenkov counters for energy determination between 5 and 90 GeV per nucleon, has been exposed for a net total of 4.5 m/sup 2/ sr hr in two balloon flights in 1974. The measurement yields the chemical composition and energy spectra of cosmic-ray nuclei in the charge range 5< or =Z< or =28. The differential spectral indices of oxygen and of the iron group are measured to be 2.67 +- 0.04 and 2.50 +- 0.08 above 5.4 GeV per nucleon, respectively. The results are interpreted in the context of the ''leaky-box'' model of cosmic-ray confinement and propagation. The cosmic-ray leakage path length lambda is found to have the energy dependence lambdaproportionalE/sup -0.59plus-or-minus0.09//sub tot/. After this energy-dependent propagation has been incorporated into the model, it is found that the measurements are consistent with an energy-independent source composition for the cosmic rays.

• Research Organization: Enrico Fermi Institute and Department of Physics, University of Chicago
• OSTI ID: 5236449
• Journal Information: Astrophys. J.; (United States), Journal Name: Astrophys. J.; (United States) Vol. 218:1; ISSN ASJOA
• Country of Publication: United States
• Language: English

Related Subjects

640101* -- Astrophysics &amp; Cosmology-- Cosmic Radiation
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
ABUNDANCE
CHEMICAL COMPOSITION
CHERENKOV COUNTERS
COSMIC NUCLEI
COSMIC RADIATION
ENERGY SPECTRA
IONIZING RADIATIONS
MEASURING INSTRUMENTS
NUCLEI
PRIMARY COSMIC RADIATION
RADIATION DETECTORS
RADIATIONS
SPECTRA
TELESCOPE COUNTERS