Dependence of IMF By penetration into the neutral sheet on IMF Bz and geomagnetic activity. Issue 7 (2nd July 2014)

• Record Type: Journal Article
• Authors: Cao, JinBin; Duan, Aiying; Dunlop, M.; Wei, Xinhua; Cai, Cunlin
• Is Part Of: Journal of geophysical research. Volume 119:Issue 7(2014:Jul.)
• Page Start: 5279
• Page End: 5285
• Publication Date: 2014-07-02
• Subjects: Magnetospheric physics -- Periodicals; Space environment -- Periodicals; Cosmic physics -- Periodicals; Planets -- Atmospheres -- Periodicals; Heliosphere (Astrophysics) -- Periodicals; Geophysics -- Periodicals; 523.01
• DOI: 10.1002/2014JA019827
• Languages: English
• ISSNs: 2169-9380

Abstract

<abstract abstract-type="main"> <title>Abstract</title> <p>The penetration of interplanetary magnetic field (IMF) <italic>B<sub>y</sub></italic> into the magnetosphere plays an important role in determining magnetospheric configuration and its dynamics. In this paper, using 9 years of Cluster data at the center of neutral sheet, we statistically study the relations of the penetration of IMF <italic>B<sub>y</sub></italic> in the neutral sheet (NS) with IMF <italic>B<sub>z</sub></italic> and the <italic>Kp</italic> index. The correlation coefficient between NS <italic>B<sub>y</sub></italic> and IMF <italic>B<sub>y</sub></italic> is enhanced during the periods of southward IMF <italic>B<sub>z</sub></italic> and large <italic>Kp</italic> indexes. The penetration efficiency of IMF <italic>B<sub>y</sub></italic>, which is defined as the slope of the linear fit of the points in the <italic>B<sub>y</sub></italic>‐IMF <italic>B<sub>y</sub></italic> space, is larger during southward IMF <italic>B<sub>z</sub></italic> than during northward IMF <italic>B<sub>z</sub></italic>. The penetration efficiency of IMF <italic>B<sub>y</sub></italic> also increases with increasing <italic>Kp</italic> index. Since the <italic>Kp</italic> index can be considered as an index of magnetospheric convection, this means that the penetration of IMF <italic>B<sub>y</sub></italic> into the magnetosphere is enhanced during the periods of strong magnetospheric convection. These results indicate that the IMF <italic>B<sub>z</sub></italic> and magnetospheric convection can influence the neutral sheet <italic>B<sub>y</sub></italic> and even magnetotail dynamics by changing the penetration of IMF <italic>B<sub>y</sub></italic>.</p> </abstract>