Search: id:"swepub:oai:DiVA.org:kth-253249" >
Pitch angle distrib...
-
Fu, H. S.Uppsala universitet,Institutet för rymdfysik, Uppsalaavdelningen,Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen
(author)
Pitch angle distribution of suprathermal electrons behind dipolarization fronts : A statistical overview
- Article/chapterEnglish2012
Publisher, publication year, extent ...
-
American Geophysical Union (AGU),2012
-
printrdacarrier
Numbers
-
LIBRIS-ID:oai:DiVA.org:kth-253249
-
https://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-253249URI
-
https://doi.org/10.1029/2012JA018141DOI
-
https://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-191766URI
Supplementary language notes
-
Language:English
-
Summary in:English
Part of subdatabase
Classification
-
Subject category:ref swepub-contenttype
-
Subject category:art swepub-publicationtype
Notes
-
QC 20190625
-
We examine the pitch angle distribution (PAD) of suprathermal electrons (> 40 keV) inside the flux pileup regions (FPRs) that are located behind the dipolarization fronts (DFs), in order to better understand the particle energization mechanisms operating therein. The 303 earthward-propagating DFs observed during 9 years (2001-2009) by Cluster 1 have been analyzed and divided into two groups according to the differential fluxes of the > 40 keV electrons inside the FPR. One group, characterized by the low flux (F < 500/cm(2) , s . sr . keV), consists of 153 events and corresponds to a broad distribution of IMF Bz components. The other group, characterized by the high flux (F >= 500/cm(2) . s . sr . keV), consists of 150 events and corresponds to southward IMF Bz components. Only the high-flux group is considered to investigate the PAD of the > 40 keV electrons as the low-flux situation may lead to large uncertainties in computing the anisotropy factor that is defined as A = F-perpendicular to/F-parallel to - 1 for F-perpendicular to > F-parallel to, and A = -F-parallel to/F-perpendicular to + 1 for F-perpendicular to < F-parallel to. We find that, among the 150 events, 46 events have isotropic distribution (vertical bar A vertical bar <= 0.5); 60 events have perpendicular distribution (A > 0.5), and 44 events have field-aligned distribution inside the FPR (A < -0.5). The perpendicular distribution appears mainly inside the growing FPR, where the flow velocity is increasing and the local flux tube is compressed. The field-aligned distribution occurs mainly inside the decaying FPR, where the flow velocity is decreasing and the local flux tube is expanding. Inside the steady FPR, we observed primarily the isotropic distribution of suprathermal electrons. This statistical result confirms the previous case study and gives an overview of the PAD of suprathermal electrons behind DFs.
Added entries (persons, corporate bodies, meetings, titles ...)
-
Khotyaintsev, Y. V.Uppsala universitet,Institutet för rymdfysik, Uppsalaavdelningen,Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen(Swepub:uu)ykh28990
(author)
-
Vaivads, AndrisUppsala universitet,Institutet för rymdfysik, Uppsalaavdelningen,Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen(Swepub:uu)anvai517
(author)
-
Andre, M.Uppsala universitet,Institutet för rymdfysik, Uppsalaavdelningen,Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen(Swepub:uu)maand125
(author)
-
Sergeev, V. A.
(author)
-
Huang, S. Y.Uppsala universitet,Institutet för rymdfysik, Uppsalaavdelningen,Uppsala universitet, Institutet för rymdfysik, Uppsalaavdelningen
(author)
-
Kronberg, E. A.
(author)
-
Daly, P. W.
(author)
-
Uppsala universitetInstitutet för rymdfysik, Uppsalaavdelningen
(creator_code:org_t)
Related titles
-
In:Journal of Geophysical Research: American Geophysical Union (AGU)117:120148-02272156-2202
Internet link
Find in a library
To the university's database