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Neptune's cosmic ray cutoff

Selesnick, R. S. and Stone, E. C. (1991) Neptune's cosmic ray cutoff. Geophysical Research Letters, 18 (3). pp. 361-364. ISSN 0094-8276. doi:10.1029/90GL02582.

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The Voyager 2 cosmic ray experiment observed the signature of a magnetic cutoff of cosmic ray protons immediately after the closest approach to Neptune. The cutoff signature shows that the simultaneous observation of a trapped particle dropout could not have occurred at high magnetic latitudes, but is likely to be a drift shadow of the planet caused by the large offset of the particle drift shells. The OTD2 dipole model of Neptune's magnetic field predicts a drift shadow at approximately the correct times. In addition, the cutoff signature is similar to that predicted by the OTD2 model, although the model is not accurate throughout the observation period. The similarity is consistent with small estimated corrections to the predicted signature based on the locally observed magnetic field values, indicating that the L shell values derived from the model are approximately valid after the closest approach time.

Item Type:Article
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URLURL TypeDescription DOIArticle
Stone, E. C.0000-0002-2010-5462
Additional Information:© 1991 American Geophysical Union. Received: August 14, 1990; revised: October 18, 1990; accepted: November 26, 1990. We thank N. F. Ness for supplying magnetic field data and the OTD2 model prior to publication. This work was supported by NASA under contract NAS7-918 and grant NGR 05-002-160.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
NASANGR 05-002-160
Issue or Number:3
Record Number:CaltechAUTHORS:20140305-131928874
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Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:44157
Deposited By: Tony Diaz
Deposited On:07 Mar 2014 17:28
Last Modified:10 Nov 2021 16:48

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