Abstract
Anomalous electron heat fluxes and recent observations of day‐night asymmetries in polar wind features indicate that photoelectrons may affect polar wind dynamics. These anomalous fluxes require a global kinetic description (i.e., mesoscale particle phase space evolution involving microscale interactions); their impact on the polar wind itself requires a self‐consistent description. In this Letter, we discuss results of a self‐consistent hybrid model that explains the dayside observations. This model represents the first global kinetic collisional description for photoelectrons in a self‐consistent classical polar wind picture. In this model, photoelectrons are treated as test particles, ion properties are based on global kinetic collisional calculations, thermal electron features and the ambipolar field are determined by fluid calculations. The model provides the first global steady‐state polar wind solution that is continuous from the subsonic collisional regime at low altitude to the supersonic collisionless regime at high altitude. Also, the results are consistent with experiments in several aspects, such as order of magnitude of the ambipolar electric potential, qualitative features of the ion outflow characteristics, electron anisotropy and upwardly directed electron heat flux on the dayside.
| Original language | English |
|---|---|
| Pages (from-to) | 2107-2110 |
| Number of pages | 4 |
| Journal | Geophysical Research Letters |
| Volume | 22 |
| Issue number | 16 |
| DOIs | |
| Publication status | Published - 1995 Jan 1 |
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All Science Journal Classification (ASJC) codes
- Geophysics
- Earth and Planetary Sciences(all)
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Self‐consistent kinetic photoelectron effects on the polar wind. / Tam, Sunny Wing-Yee; Yasseen, Fareed; Chang, Tom; Ganguli, Supriya B.
In: Geophysical Research Letters, Vol. 22, No. 16, 01.01.1995, p. 2107-2110.Research output: Contribution to journal › Article
TY - JOUR
T1 - Self‐consistent kinetic photoelectron effects on the polar wind
AU - Tam, Sunny Wing-Yee
AU - Yasseen, Fareed
AU - Chang, Tom
AU - Ganguli, Supriya B.
PY - 1995/1/1
Y1 - 1995/1/1
N2 - Anomalous electron heat fluxes and recent observations of day‐night asymmetries in polar wind features indicate that photoelectrons may affect polar wind dynamics. These anomalous fluxes require a global kinetic description (i.e., mesoscale particle phase space evolution involving microscale interactions); their impact on the polar wind itself requires a self‐consistent description. In this Letter, we discuss results of a self‐consistent hybrid model that explains the dayside observations. This model represents the first global kinetic collisional description for photoelectrons in a self‐consistent classical polar wind picture. In this model, photoelectrons are treated as test particles, ion properties are based on global kinetic collisional calculations, thermal electron features and the ambipolar field are determined by fluid calculations. The model provides the first global steady‐state polar wind solution that is continuous from the subsonic collisional regime at low altitude to the supersonic collisionless regime at high altitude. Also, the results are consistent with experiments in several aspects, such as order of magnitude of the ambipolar electric potential, qualitative features of the ion outflow characteristics, electron anisotropy and upwardly directed electron heat flux on the dayside.
AB - Anomalous electron heat fluxes and recent observations of day‐night asymmetries in polar wind features indicate that photoelectrons may affect polar wind dynamics. These anomalous fluxes require a global kinetic description (i.e., mesoscale particle phase space evolution involving microscale interactions); their impact on the polar wind itself requires a self‐consistent description. In this Letter, we discuss results of a self‐consistent hybrid model that explains the dayside observations. This model represents the first global kinetic collisional description for photoelectrons in a self‐consistent classical polar wind picture. In this model, photoelectrons are treated as test particles, ion properties are based on global kinetic collisional calculations, thermal electron features and the ambipolar field are determined by fluid calculations. The model provides the first global steady‐state polar wind solution that is continuous from the subsonic collisional regime at low altitude to the supersonic collisionless regime at high altitude. Also, the results are consistent with experiments in several aspects, such as order of magnitude of the ambipolar electric potential, qualitative features of the ion outflow characteristics, electron anisotropy and upwardly directed electron heat flux on the dayside.
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UR - http://www.scopus.com/inward/citedby.url?scp=0029502457&partnerID=8YFLogxK
U2 - 10.1029/95GL01846
DO - 10.1029/95GL01846
M3 - Article
AN - SCOPUS:0029502457
VL - 22
SP - 2107
EP - 2110
JO - Geophysical Research Letters
JF - Geophysical Research Letters
SN - 0094-8276
IS - 16
ER -