Electron Acceleration in the Heart of the Van Allen Radiation Belts.

Saved in:

Bibliographic Details
Title:	Electron Acceleration in the Heart of the Van Allen Radiation Belts.
Authors:	Reeves, G. D., Spence, H. E., Henderson, M. G., Morley, S. K., Friedel, R. H. W., Funsten, H. 0., Baker, D. N., Kanekal, S. G., Blake, J. B., Fennell, J. F., Claudepierre, S. G., Thome, R. M., Turner, D. L., Kletzing, C. A., Kurth, W. S., Larsen, B. A., Niehof, J. T.
Source:	Science (pre-March 2025). 8/30/2013, Vol. 341 Issue 6149, p991-994. 4p.
Subjects:	Van Allen radiation belts, Relativistic electrons, Geomagnetism, Particle acceleration, Centripetal acceleration, Acceleration (Mechanics)
Abstract:	The Van Allen radiation belts contain ultrarelativistic electrons trapped in Earth's magnetic field. Since their discovery in 1958, a fundamental unanswered question has been how electrons can be accelerated to such high energies. Two classes of processes have been proposed: transport and acceleration of electrons from a source population located outside the radiation belts (radial acceleration) or acceleration of lower-energy electrons to relativistic energies in situ in the heart of the radiation belts (local acceleration). We report measurements from NASA's Van Allen Radiation Belt Storm Probes that clearly distinguish between the two types of acceleration. The observed radial profiles of phase space density are characteristic of local acceleration in the heart of the radiation belts and are inconsistent with a predominantly radial acceleration process. [ABSTRACT FROM AUTHOR]
	Copyright of Science (pre-March 2025) is the property of American Association for the Advancement of Science and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database:	Psychology and Behavioral Sciences Collection

Description
Abstract:	The Van Allen radiation belts contain ultrarelativistic electrons trapped in Earth's magnetic field. Since their discovery in 1958, a fundamental unanswered question has been how electrons can be accelerated to such high energies. Two classes of processes have been proposed: transport and acceleration of electrons from a source population located outside the radiation belts (radial acceleration) or acceleration of lower-energy electrons to relativistic energies in situ in the heart of the radiation belts (local acceleration). We report measurements from NASA's Van Allen Radiation Belt Storm Probes that clearly distinguish between the two types of acceleration. The observed radial profiles of phase space density are characteristic of local acceleration in the heart of the radiation belts and are inconsistent with a predominantly radial acceleration process. [ABSTRACT FROM AUTHOR]
ISSN:	00368075
DOI:	10.1126/science.1237743