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Title: Dynamics of low-energy electrons (> or =17 keV) and ions (> or =80 keV) in the vicinity of the low-latitude, Duskside magnetopause: Helios 1 and 2 observations

Abstract

The space probes Helios 1 and 2 left the earth's magnetosphere to enter heliocentric orbits on the duskside, at nearly zero latitude, and in the dusk-noon quadrant. During this perid, electron and ion observations with E/sub e/> or =17 keV and E/sub i/> or =80 keV and with high time (13.5 s), energy (16 energy channels), and directional (16 sectors) resolutions were performed by the low-energetic-particle spectrometer of the Max-Planck-Institut fuer Aeronomie and magnetic field measurements by the flux-gate magnetometer of the Institut fuer Geophysik und Meteorologie. At the magnetopause these particle and field observations indicate the following: (1) There is a > or =17-keV electron and > or =80-keV ion layer at the magnetopause. (2) In this layer the ion spectra are bipower law spectra with ..gamma../sub i/approx. =7 for E/sub i/<200 keV and ..gamma../sub i/approx. =3 for E/sub i/> or =200 keV. For electrons of <70 keV we find power law spectra with ..gamma../sub e/approx. =5. (3)The actually observed energy flows (erg/s) associated with the ions are 1.1 x 10/sup 18/-- 2.1 x 10/sup 19/ (E/sub greater-than-or-equal/80 keV, Helios 1) and 1.2 x 10/sup 17/ (E/sub i/> or =87 keV, Helios 2), and those associated with the electronsmore » 8 x 10/sup 15/ (E/sub e/> or =17 keV, Helios 1) and 1.8 x 10/sup 16/ (E/sub e/> or =20 keV, Helios 2), if a homogeneous layer over the entire magnetopause is assumed. An energy flow of 10/sup 18/--10/sup 19/ ergs/s is required for a dayside reconnection in the earth's magnetosphere (Keikkila 1975). (4) The number of ions (electrons) per second carrying 10/sup 18/ ergs/s is 3 (1) orders of magnitude smaller than the number of solar wind particles arriving at the magnetopause, as estimated by Keikkila (1975). (5) Magnetic field and directional observations of > or =17-keV electrons indicate that the magnetopause at least at these latitudes is near an X line or X-type neutral line.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Max-Planck-Institut fuer Aeronomie, Katlenburg-Lindau, West Germany
OSTI Identifier:
6215471
Resource Type:
Journal Article
Journal Name:
J. Geophys. Res.; (United States)
Additional Journal Information:
Journal Volume: 84:A4
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; MAGNETOPAUSE; ELECTRONS; IONS; INTERPLANETARY MAGNETIC FIELDS; KEV RANGE; MAGNETIC FIELD CONFIGURATIONS; PLASMA ACCELERATION; SOLAR WIND; ACCELERATION; CHARGED PARTICLES; ELEMENTARY PARTICLES; ENERGY RANGE; FERMIONS; LEPTONS; MAGNETIC FIELDS; SOLAR ACTIVITY; 640203* - Atmospheric Physics- Magnetospheric Phenomena- (-1987)

Citation Formats

Richter, A K, Keppler, E, Axford, W I, and Denskat, K U. Dynamics of low-energy electrons (> or =17 keV) and ions (> or =80 keV) in the vicinity of the low-latitude, Duskside magnetopause: Helios 1 and 2 observations. United States: N. p., 1979. Web. doi:10.1029/JA084iA04p01453.
Richter, A K, Keppler, E, Axford, W I, & Denskat, K U. Dynamics of low-energy electrons (> or =17 keV) and ions (> or =80 keV) in the vicinity of the low-latitude, Duskside magnetopause: Helios 1 and 2 observations. United States. doi:10.1029/JA084iA04p01453.
Richter, A K, Keppler, E, Axford, W I, and Denskat, K U. Sun . "Dynamics of low-energy electrons (> or =17 keV) and ions (> or =80 keV) in the vicinity of the low-latitude, Duskside magnetopause: Helios 1 and 2 observations". United States. doi:10.1029/JA084iA04p01453.
@article{osti_6215471,
title = {Dynamics of low-energy electrons (> or =17 keV) and ions (> or =80 keV) in the vicinity of the low-latitude, Duskside magnetopause: Helios 1 and 2 observations},
author = {Richter, A K and Keppler, E and Axford, W I and Denskat, K U},
abstractNote = {The space probes Helios 1 and 2 left the earth's magnetosphere to enter heliocentric orbits on the duskside, at nearly zero latitude, and in the dusk-noon quadrant. During this perid, electron and ion observations with E/sub e/> or =17 keV and E/sub i/> or =80 keV and with high time (13.5 s), energy (16 energy channels), and directional (16 sectors) resolutions were performed by the low-energetic-particle spectrometer of the Max-Planck-Institut fuer Aeronomie and magnetic field measurements by the flux-gate magnetometer of the Institut fuer Geophysik und Meteorologie. At the magnetopause these particle and field observations indicate the following: (1) There is a > or =17-keV electron and > or =80-keV ion layer at the magnetopause. (2) In this layer the ion spectra are bipower law spectra with ..gamma../sub i/approx. =7 for E/sub i/<200 keV and ..gamma../sub i/approx. =3 for E/sub i/> or =200 keV. For electrons of <70 keV we find power law spectra with ..gamma../sub e/approx. =5. (3)The actually observed energy flows (erg/s) associated with the ions are 1.1 x 10/sup 18/-- 2.1 x 10/sup 19/ (E/sub greater-than-or-equal/80 keV, Helios 1) and 1.2 x 10/sup 17/ (E/sub i/> or =87 keV, Helios 2), and those associated with the electrons 8 x 10/sup 15/ (E/sub e/> or =17 keV, Helios 1) and 1.8 x 10/sup 16/ (E/sub e/> or =20 keV, Helios 2), if a homogeneous layer over the entire magnetopause is assumed. An energy flow of 10/sup 18/--10/sup 19/ ergs/s is required for a dayside reconnection in the earth's magnetosphere (Keikkila 1975). (4) The number of ions (electrons) per second carrying 10/sup 18/ ergs/s is 3 (1) orders of magnitude smaller than the number of solar wind particles arriving at the magnetopause, as estimated by Keikkila (1975). (5) Magnetic field and directional observations of > or =17-keV electrons indicate that the magnetopause at least at these latitudes is near an X line or X-type neutral line.},
doi = {10.1029/JA084iA04p01453},
journal = {J. Geophys. Res.; (United States)},
number = ,
volume = 84:A4,
place = {United States},
year = {1979},
month = {4}
}