Day-night asymmetry of polar outflow due to the kinetic effects of anisotropic photoelectrons

Sunny Wing-Yee Tam, Fareed Yasseen, Tom Chang

Research output: Chapter in Book/Report/Conference proceedingChapter

1 Citation (Scopus)

Abstract

Recent polar wind measurements between 5000 and 9000 km altitude by the Akebono satellite indicate that both H+ and O+ ions can have remarkably higher outflow velocities in the sunlit region than on the nightside. In addition, electrons also display an asymmetric behavior: the dayside difference in energy spread, greater for upward-moving than downward-moving electrons, is absent on the nightside. We use a self-consistent hybrid model [Tam et ai, 1995b] that was developed for the polar wind outflow to address these observed day-night asymmetric features. The model takes into account the evolution of the polar wind self-consistently by properly recognizing the global, kinetic, collisional effects of the sunlit photoelectrons. By studying the effects of the presence and absence of photoelectrons on the polar outflow, we compare the daytime and night-time polar wind results, and demonstrate the asymmetries observed by the Akebono satellite.

Original languageEnglish
Title of host publicationGeospace Mass and Energy Flow
Subtitle of host publicationResults From the International Solar-Terrestrial Physics Program, 1998
EditorsJames L. Horwitz, William K. Peterson, Dennis L. Gallagher
PublisherBlackwell Publishing Ltd
Pages97-106
Number of pages10
ISBN (Electronic)9781118664162
ISBN (Print)9780875900872
DOIs
Publication statusPublished - 1998 Jan 1

Publication series

NameGeophysical Monograph Series
Volume104
ISSN (Print)0065-8448
ISSN (Electronic)2328-8779

Fingerprint

EXOS-D satellite
night
asymmetry
photoelectrons
outflow
kinetics
wind measurement
electron
daytime
electrons
ion
energy
effect
ions

All Science Journal Classification (ASJC) codes

  • Geophysics

Cite this

Tam, S. W-Y., Yasseen, F., & Chang, T. (1998). Day-night asymmetry of polar outflow due to the kinetic effects of anisotropic photoelectrons. In J. L. Horwitz, W. K. Peterson, & D. L. Gallagher (Eds.), Geospace Mass and Energy Flow: Results From the International Solar-Terrestrial Physics Program, 1998 (pp. 97-106). (Geophysical Monograph Series; Vol. 104). Blackwell Publishing Ltd. https://doi.org/10.1029/GM104p0097
Tam, Sunny Wing-Yee ; Yasseen, Fareed ; Chang, Tom. / Day-night asymmetry of polar outflow due to the kinetic effects of anisotropic photoelectrons. Geospace Mass and Energy Flow: Results From the International Solar-Terrestrial Physics Program, 1998. editor / James L. Horwitz ; William K. Peterson ; Dennis L. Gallagher. Blackwell Publishing Ltd, 1998. pp. 97-106 (Geophysical Monograph Series).
@inbook{423022afea90465193e3c64d979dfdeb,
title = "Day-night asymmetry of polar outflow due to the kinetic effects of anisotropic photoelectrons",
abstract = "Recent polar wind measurements between 5000 and 9000 km altitude by the Akebono satellite indicate that both H+ and O+ ions can have remarkably higher outflow velocities in the sunlit region than on the nightside. In addition, electrons also display an asymmetric behavior: the dayside difference in energy spread, greater for upward-moving than downward-moving electrons, is absent on the nightside. We use a self-consistent hybrid model [Tam et ai, 1995b] that was developed for the polar wind outflow to address these observed day-night asymmetric features. The model takes into account the evolution of the polar wind self-consistently by properly recognizing the global, kinetic, collisional effects of the sunlit photoelectrons. By studying the effects of the presence and absence of photoelectrons on the polar outflow, we compare the daytime and night-time polar wind results, and demonstrate the asymmetries observed by the Akebono satellite.",
author = "Tam, {Sunny Wing-Yee} and Fareed Yasseen and Tom Chang",
year = "1998",
month = "1",
day = "1",
doi = "10.1029/GM104p0097",
language = "English",
isbn = "9780875900872",
series = "Geophysical Monograph Series",
publisher = "Blackwell Publishing Ltd",
pages = "97--106",
editor = "Horwitz, {James L.} and Peterson, {William K.} and Gallagher, {Dennis L.}",
booktitle = "Geospace Mass and Energy Flow",

}

Tam, SW-Y, Yasseen, F & Chang, T 1998, Day-night asymmetry of polar outflow due to the kinetic effects of anisotropic photoelectrons. in JL Horwitz, WK Peterson & DL Gallagher (eds), Geospace Mass and Energy Flow: Results From the International Solar-Terrestrial Physics Program, 1998. Geophysical Monograph Series, vol. 104, Blackwell Publishing Ltd, pp. 97-106. https://doi.org/10.1029/GM104p0097

Day-night asymmetry of polar outflow due to the kinetic effects of anisotropic photoelectrons. / Tam, Sunny Wing-Yee; Yasseen, Fareed; Chang, Tom.

Geospace Mass and Energy Flow: Results From the International Solar-Terrestrial Physics Program, 1998. ed. / James L. Horwitz; William K. Peterson; Dennis L. Gallagher. Blackwell Publishing Ltd, 1998. p. 97-106 (Geophysical Monograph Series; Vol. 104).

Research output: Chapter in Book/Report/Conference proceedingChapter

TY - CHAP

T1 - Day-night asymmetry of polar outflow due to the kinetic effects of anisotropic photoelectrons

AU - Tam, Sunny Wing-Yee

AU - Yasseen, Fareed

AU - Chang, Tom

PY - 1998/1/1

Y1 - 1998/1/1

N2 - Recent polar wind measurements between 5000 and 9000 km altitude by the Akebono satellite indicate that both H+ and O+ ions can have remarkably higher outflow velocities in the sunlit region than on the nightside. In addition, electrons also display an asymmetric behavior: the dayside difference in energy spread, greater for upward-moving than downward-moving electrons, is absent on the nightside. We use a self-consistent hybrid model [Tam et ai, 1995b] that was developed for the polar wind outflow to address these observed day-night asymmetric features. The model takes into account the evolution of the polar wind self-consistently by properly recognizing the global, kinetic, collisional effects of the sunlit photoelectrons. By studying the effects of the presence and absence of photoelectrons on the polar outflow, we compare the daytime and night-time polar wind results, and demonstrate the asymmetries observed by the Akebono satellite.

AB - Recent polar wind measurements between 5000 and 9000 km altitude by the Akebono satellite indicate that both H+ and O+ ions can have remarkably higher outflow velocities in the sunlit region than on the nightside. In addition, electrons also display an asymmetric behavior: the dayside difference in energy spread, greater for upward-moving than downward-moving electrons, is absent on the nightside. We use a self-consistent hybrid model [Tam et ai, 1995b] that was developed for the polar wind outflow to address these observed day-night asymmetric features. The model takes into account the evolution of the polar wind self-consistently by properly recognizing the global, kinetic, collisional effects of the sunlit photoelectrons. By studying the effects of the presence and absence of photoelectrons on the polar outflow, we compare the daytime and night-time polar wind results, and demonstrate the asymmetries observed by the Akebono satellite.

UR - http://www.scopus.com/inward/record.url?scp=36148932526&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=36148932526&partnerID=8YFLogxK

U2 - 10.1029/GM104p0097

DO - 10.1029/GM104p0097

M3 - Chapter

AN - SCOPUS:36148932526

SN - 9780875900872

T3 - Geophysical Monograph Series

SP - 97

EP - 106

BT - Geospace Mass and Energy Flow

A2 - Horwitz, James L.

A2 - Peterson, William K.

A2 - Gallagher, Dennis L.

PB - Blackwell Publishing Ltd

ER -

Tam SW-Y, Yasseen F, Chang T. Day-night asymmetry of polar outflow due to the kinetic effects of anisotropic photoelectrons. In Horwitz JL, Peterson WK, Gallagher DL, editors, Geospace Mass and Energy Flow: Results From the International Solar-Terrestrial Physics Program, 1998. Blackwell Publishing Ltd. 1998. p. 97-106. (Geophysical Monograph Series). https://doi.org/10.1029/GM104p0097