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The Energy Spectrum of 0.16 to 2 MeV Electrons During Solar Quiet Times

Hurford, G. J. and Mewaldt, R. A. and Stone, E. C. and Vogt, R. E. (1974) The Energy Spectrum of 0.16 to 2 MeV Electrons During Solar Quiet Times. Astrophysical Journal, 192 . pp. 541-546. ISSN 0004-637X. doi:10.1086/153088.

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New observations of the quiet-time energy spectrum of 0.16- to 2-MeV electrons have been made with the Caltech Electron/Isotope Spectrometer which was launched on IMP-7 in September 1972. Earlier measurements of quiet-time electrons in this energy range by other groups have resulted in spectra differing by more than an order of magnitude in intensity. A minimum quiet-time flux level somewhat lower than the lowest previously reported spectra and consistent with an extrapolation of the spectrum measured at higher energies is found. A galactic secondary source of knock-on electrons is consistent with these results and with independent studies of the interstellar spectra of cosmic-ray nuclei, provided that solar modulation does not suppress the 0.16- to 2-MeV electron flux by more than a factor of about 3. Although not required, other recently suggested sources may also contribute to the observed fluxes.

Item Type:Article
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Mewaldt, R. A.0000-0003-2178-9111
Stone, E. C.0000-0002-2010-5462
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Additional Information:© 1974. The American Astronomical Society. Received 1974 February 12. Dr. J. E. Lupton and W. E. Althouse made significant contributions to the design and development of the Electron/Isotope Spectrometer. This work was supported in part by the National Aeronautics and Space Administration under contract NAS5-11066 and grant NGR 05-002-160. One of us (G. J. H.) received support from the National Research Council of Canada while another (E. C. S.) was an Alfred P. Sloan research fellow during this period.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
NASANGR 05-002-160
National Research Council of CanadaUNSPECIFIED
Alfred P. Sloan FoundationUNSPECIFIED
Subject Keywords:cosmic rays
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Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1974-01
Record Number:CaltechAUTHORS:20140409-093732830
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:44816
Deposited By: SWORD User
Deposited On:11 Apr 2014 19:05
Last Modified:10 Nov 2021 16:56

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