English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT
  Acceleration of protons and heavy ions to suprathermal energies during dipolarizations in the near-Earth magnetotail

Malykhin, A. Y., Grigorenko, E. E., Kronberg, E. A., Daly, P. W., & Kozak, L. V. (2019). Acceleration of protons and heavy ions to suprathermal energies during dipolarizations in the near-Earth magnetotail. Annales Geophysicae, 37(4), 549-559. doi:10.5194/angeo-37-549-2019.

Item is

Basic

show hide
Item Permalink: http://hdl.handle.net/21.11116/0000-0004-0267-6 Version Permalink: http://hdl.handle.net/21.11116/0000-0005-0B00-F
Genre: Journal Article

Files

show Files

Locators

show

Creators

show
hide
 Creators:
Malykhin, Andrei Y., Author
Grigorenko, Elena E., Author
Kronberg, Elena A.1, Author              
Daly, Patrick W.1, Author              
Kozak, Ludmila V., Author
Affiliations:
1Department Planets and Comets, Max Planck Institute for Solar System Research, Max Planck Society, ou_1832288              

Content

show
hide
Free keywords: -
 Abstract: In this work we present an analysis of the dynamics of suprathermal ions of different masses (H+, He+, O+) during prolonged dipolarizations in the near-Earth magnetotail (X>−17RE) according to Cluster/RAPID observations in 2001–2005. All dipolarizations from our database were associated with fast flow braking and consisted of multiple dipolarization fronts (DFs). We found statistically that fluxes of suprathermal ions started to increase ∼1 min before the dipolarization onset and continued to grow for ∼1 min after the onset. The start of flux growth coincided with the beginning of a decrease in the spectral index γ. The decrease in γ was observed for protons for ∼1 min after the dipolarization onset, and for He+ and O+ ions for ∼3 and ∼5 min after the onset respectively. The negative variations of γ for O+ ions were ∼2.5 times larger than for light ions. This demonstrates more efficient acceleration for heavy ions. The strong negative variations of γ were observed in finite energy ranges for all ion components. This indicates the possibility of nonadiabatic resonant acceleration of ions in the course of their interaction with multiple DFs during dipolarizations. Our analysis showed that some fraction of light ions can be accelerated up to energies ≥600 keV and some fraction of oxygen ions can be accelerated up to ∼1.2 MeV. Such strong energy gains cannot be explained by acceleration at a single propagating DF and suggest the possibility of multistage ion acceleration in the course of their interaction with multiple DFs during the prolonged dipolarizations.

Details

show
hide
Language(s): eng - English
 Dates: 2019
 Publication Status: Published in print
 Pages: -
 Publishing info: -
 Table of Contents: -
 Rev. Method: Peer
 Identifiers: DOI: 10.5194/angeo-37-549-2019
 Degree: -

Event

show

Legal Case

show

Project information

show

Source 1

show
hide
Title: Annales Geophysicae
Source Genre: Journal
 Creator(s):
Affiliations:
Publ. Info: Montrouge Cedex, France : Gauthier-Villars
Pages: - Volume / Issue: 37 (4) Sequence Number: - Start / End Page: 549 - 559 Identifier: ISSN: 0992-7689
CoNE: https://pure.mpg.de/cone/journals/resource/954928606127