A Caltech Library Service

Radial and Latitudinal Gradients of Anomalous Cosmic Rays in the Outer Heliosphere

Stone, E. C. and Cummings, A. C. and Webber, W. R. (1995) Radial and Latitudinal Gradients of Anomalous Cosmic Rays in the Outer Heliosphere. In: Proceedings of the 24th International Cosmic Ray Conference. Vol.4. International Union of Pure and Applied Physics , pp. 796-799.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We use recent data from the Voyager 1 and 2 and Pioneer 10 spacecraft to determine the radial and latitudinal gradients of anomalous cosmic rays (ACRs) in the outer heliosphere. The latitudinal gradient is small and positive, as opposed to the large and negative values observed during the last solar minimum in 1987. The radial gradient is small and steady. We compare our results with current theories of the acceleration and propagation of ACRs. We also suggest that the large increase in the intensity of ACR helium that we observe during 1992 is due primarily to a change in · the ACR source flux as interplanetary conditions approach quasi-equilibrium. The continuing increases at lower energies in 1993 and 1994 are consistent with a decreasing level of modulation during a period of quasi-equilibrium.

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Stone, E. C.0000-0002-2010-5462
Cummings, A. C.0000-0002-3840-7696
Additional Information:© IUPAP. Provided by the NASA Astrophysics Data System. This work was supported in part by NASA under contract NAS7-918 and grant NAGW-1919. We thank J. T. Hoeksema for providing the tilt observations prior to publication.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1995-19
Record Number:CaltechAUTHORS:20140616-163700853
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:46290
Deposited By: Deborah Miles
Deposited On:24 Jun 2014 18:05
Last Modified:20 Feb 2020 14:33

Repository Staff Only: item control page