scholarly journals Resonant scattering of central plasma sheet protons by multiband EMIC waves and resultant proton loss timescales

2016 ◽  
Vol 121 (2) ◽  
pp. 1219-1232 ◽  
Author(s):  
Xing Cao ◽  
Binbin Ni ◽  
Jun Liang ◽  
Zheng Xiang ◽  
Qi Wang ◽  
...  
2011 ◽  
Vol 116 (A9) ◽  
pp. n/a-n/a ◽  
Author(s):  
Bingxian Luo ◽  
Weichao Tu ◽  
Xinlin Li ◽  
Jiancun Gong ◽  
Siqing Liu ◽  
...  

2016 ◽  
Vol 34 (2) ◽  
pp. 249-257 ◽  
Author(s):  
Ying Xiong ◽  
Zhigang Yuan ◽  
Jingfang Wang

Abstract. In this paper, we report in situ observations by the Cluster spacecraft of energetic ions scattered into the loss cone during the inbound pass from the plasma sheet into the plasmasphere. During the inbound pass of the plasma sheet, Cluster observed the isotropy ratio of energetic ions to gradually decrease from unity and the isotropic boundary extended to lower L value for higher-energy ions, implying that the field line curvature scattering mechanism is responsible for the scattered ions into the loss cone from the plasma sheet. In the outer boundary of a plasmasphere plume, Cluster 3 observed the increase of the isotropy ratio of energetic ions accompanied by enhancements of Pc2 waves with frequencies between the He+ ion gyrofrequency and O+ ion gyrofrequency estimated in the equatorial plane. Those Pc2 waves were left-hand circularly polarized and identified as electromagnetic ion cyclotron (EMIC) waves. Using the observed parameters, the calculations of the pitch angle diffusion coefficients for ring current protons demonstrate that EMIC waves could be responsible for the ions scattering and loss-cone filling. Our observations provide in situ evidence of energetic ion loss in the plasma sheet and the plasmasphere plume. Our results suggest that energetic ions scattering into the loss cone in the central plasma sheet and the outer boundary of the plasmaspheric plume are attributed to the field line curvature scattering mechanism and EMIC wave scattering mechanism, respectively.


1991 ◽  
Vol 96 (A2) ◽  
pp. 1601-1609 ◽  
Author(s):  
Maha Ashour-Abdalla ◽  
Jorg Büchner ◽  
Lev M. Zelenyi

1992 ◽  
Vol 97 (A2) ◽  
pp. 1481 ◽  
Author(s):  
C. Y. Huang ◽  
L. A. Frank ◽  
G. Rostoker ◽  
J. Fennell ◽  
D. G. Mitchell

1994 ◽  
Vol 72 (5-6) ◽  
pp. 266-269 ◽  
Author(s):  
Y. I. Feldstein ◽  
R. D. Elphinstone ◽  
D. J. Hearn ◽  
J. S. Murphree ◽  
L. L. Cogger

Statistical auroral distributions are used in combination with an empirical model of the Earth's magnetic field in an attempt to determine the large-scale magnetospheric source regions for various types of auroral luminosity. The narrow ring of structured auroral emissions during magnetically quiet intervals appears to be associated with the inner region of the nightside central plasma sheet and the dayside entry layer. Under active conditions these discrete structures expand to fill the entire central plasma sheet. The high-altitude boundary plasma sheet on the other hand is more likely to be related to diffuse auroral emissions poleward of this "oval" and to high-latitude polar auroral arcs. Under this scenario, the region of the magnetosphere bounded by the inner edge of the tail current sheet, the plasmasphere, and the dayside entry layer is the source region for the most equatorward diffuse auroral precipitation.


1989 ◽  
Vol 94 (A6) ◽  
pp. 6597-6606 ◽  
Author(s):  
W. Baumjohann ◽  
G. Paschmann ◽  
C. A. Cattell

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