American Geophysical Union Become an AGU Member
Subscribe to AGU Journals		 AGU Home AGU Publications

Read Full Article (file size: 12031461 bytes)    Cited by

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 111, A04224, doi:10.1029/2005JA011342, 2006

Dependence of flux transfer events on solar wind conditions from 3 years of Cluster observations

Y. L. Wang

Space Science and Applications, Los Alamos National Laboratory, Los Alamos, New Mexico, USA


R. C. Elphic

Space Science and Applications, Los Alamos National Laboratory, Los Alamos, New Mexico, USA


B. Lavraud

Space Science and Applications, Los Alamos National Laboratory, Los Alamos, New Mexico, USA


M. G. G. T. Taylor

Space Science and Applications, Los Alamos National Laboratory, Los Alamos, New Mexico, USA
Mullard Space Science Laboratory, University College London, London, UK


J. Birn

Space Science and Applications, Los Alamos National Laboratory, Los Alamos, New Mexico, USA


C. T. Russell

Institute of Geophysics and Planetary Physics, University of California, Los Angeles, Los Angeles, California, USA


J. Raeder

Space Science Center, University of New Hampshire, Durham, New Hampshire, USA


H. Kawano

Department of Earth and Planetary Sciences, Kyushu University, Fukuoka, Japan


X. X. Zhang

Key Laboratory of Space Weather, Center for Space Science and Applied Research, Beijing, China


Abstract

We investigate the dependence of Cluster high-latitude magnetopause and low-latitude flank flux transfer events (FTEs) on solar wind conditions using measurements from Cluster FGM and CIS and ACE MFI and SWEPAM between February 2001 and June 2003. We find that there are strong dependences of Cluster FTE occurrence on the IMF B xgsm , B ygsm , and B zgsm components but not on the IMF magnitude. There are strong dependences of Cluster FTE occurrence on the IMF clock, tilt, spiral, and cone angles. However, some patterns are significantly different from previous results. The solar wind density, speed, Beta, V x B z , dynamic pressure, and magnetosonic Mach number have different degrees of control on FTE occurrence. FTE separation time is found to be clearly controlled by IMF B ygsm , B zgsm , and magnitude, and the IMF clock, tilt, spiral, and cone angles, and weakly controlled by the solar wind V x B z and magnetosonic Mach number. There is no obvious control of it by other IMF and solar wind parameters. FTE peak-peak magnitude is found to be controlled by IMF B ygsm , B zgsm , and magnitude and by the solar wind density and dynamic pressure but not by other IMF and solar wind parameters. The FTE dawn-dusk asymmetry is not likely caused by the Parker spiral IMF. Some FTE statistical patterns are strongly dependent on FTE locations. Finally, we see ∼4% of the FTEs corresponding to a single change in IMF B zgsm from positive to negative, ∼4% corresponding to a single change from negative to positive, and ∼43% corresponding to multiple changes in the sign of IMF B zgsm , all within the 10-min interval preceding the FTEs. There is still no evidence for a direct correlation between IMF B zgsm changing sign and FTEs.

Received 28 July 2005; accepted 23 January 2006; published 29 April 2006.

Keywords: cluster statistical study; flux transfer events; solar wind and IMF conditions.

Index Terms: 2784 Magnetospheric Physics: Solar wind/magnetosphere interactions; 2723 Magnetospheric Physics: Magnetic reconnection (7526, 7835); 2724 Magnetospheric Physics: Magnetopause and boundary layers; 2740 Magnetospheric Physics: Magnetospheric configuration and dynamics.

Read Full Article (file size: 12031461 bytes)    Cited by

Citation: Wang, Y. L., R. C. Elphic, B. Lavraud, M. G. G. T. Taylor, J. Birn, C. T. Russell, J. Raeder, H. Kawano, and X. X. Zhang (2006), Dependence of flux transfer events on solar wind conditions from 3 years of Cluster observations, J. Geophys. Res., 111, A04224, doi:10.1029/2005JA011342.