A Caltech Library Service

Elemental Composition of the Anomalous Cosmic-Ray Component

Cummings, A. C. and Stone, E. C. (1987) Elemental Composition of the Anomalous Cosmic-Ray Component. In: Proceedings of the 21st International Cosmic Ray Conference. Vol.3. , Nakau, Russia, pp. 413-416.

PDF - Published Version
See Usage Policy.


Use this Persistent URL to link to this item:


We report the first definitive observations of anomalous cosmic-ray (ACR) argon and carbon. Using a model for the ionization and acceleration of interstellar neutral atoms, we find A CR-derived abundances for NI, Ne I, and Ar I in the very local interstellar medium (VLISM) that are in excellent agreement with a compilation of solar system abundances, showing no evidence that significant charge-exchange processes are associated with the heliopause region. The abundance of CI is nearly 2 orders of magnitude lower than that of the solar system, indicating that most of the C in the VLISM is ionized. We find that neither of two spectroscopically determined local interstellar components have neutral compositions identical to that of the ACR-derived VLISM.

Item Type:Book Section
Related URLs:
URLURL TypeDescription
Cummings, A. C.0000-0002-3840-7696
Stone, E. C.0000-0002-2010-5462
Additional Information:© INR. Provided by the NASA Astrophysics Data System. We thank R. A. Mewaldt for many helpful discussions. We thank M. Allen for a tabulation of some of the photoionization cross sections we used. This work was supported in part by NASA under contract NAS 7-918 and grant NGR 05-002-160.
Group:Space Radiation Laboratory
Funding AgencyGrant Number
NASANGR 05-002-160
Other Numbering System:
Other Numbering System NameOther Numbering System ID
Space Radiation Laboratory1987-10
Record Number:CaltechAUTHORS:20140512-141917916
Persistent URL:
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:45699
Deposited By: Joy Painter
Deposited On:12 May 2014 21:23
Last Modified:20 Feb 2020 14:33

Repository Staff Only: item control page