Articles | Volume 33, issue 1
Ann. Geophys., 33, 1–11, 2015
https://doi.org/10.5194/angeo-33-1-2015
Ann. Geophys., 33, 1–11, 2015
https://doi.org/10.5194/angeo-33-1-2015

Regular paper 06 Jan 2015

Regular paper | 06 Jan 2015

Internally and externally induced deformations of the magnetospheric equatorial current as inferred from spacecraft data

N. A. Tsyganenko, V. A. Andreeva, and E. I. Gordeev N. A. Tsyganenko et al.
  • Institute and Faculty of Physics, Saint Petersburg State University, Saint Petersburg, Russia

Abstract. Based on a data pool of 79 yearly files of space magnetometer data by Polar, Cluster, Geotail, and THEMIS satellites between 1995 and 2013, we developed a new quantitative model of the global shape of the magnetospheric equatorial current sheet as a function of the Earth's dipole tilt angle, solar wind ram pressure, and interplanetary magnetic field (IMF). This work upgrades and generalizes an earlier model of Tsyganenko and Fairfield (2004) by extending the modeling region to all local times, including the dayside sector. In particular, an essential feature of the new model is the bowl-shaped tilt-related deformation of the equatorial surface of minimum magnetic field, similar to that observed at Saturn, whose existence in the Earth's magnetosphere has been demonstrated in our recent work (Tsyganenko and Andreeva, 2014).

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Short summary
A new quantitative model of the global shape of the neutral sheet in the Earth's magnetosphere is developed, parameterized by the dipole tilt, solar wind pressure, and IMF By and Bz. The model is based on data from the Polar, Cluster, Geotail, and Themis satellites taken in 1995-2013. The paper quantifies and further explains our earlier finding of the bowl-shaped deformation of the neutral sheet due to the Earth's dipole tilt (Tsyganenko and Andreeva, GRL, v.41(4), 2014).