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

Read Full Article (file size: 213146 bytes)    Cited by

JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 107, NO. A5, 1050, doi:10.1029/2001JA000238, 2002

Correlation of magnetic field intensities and solar wind speeds of events observed by ACE

Mathew J. Owens

Space and Atmospheric Physics, Blackett Laboratory, Imperial College, London, United Kingdom


Peter J. Cargill

Space and Atmospheric Physics, Blackett Laboratory, Imperial College, London, United Kingdom


Abstract

The relationship between the magnetic field intensity and speed of solar wind events is examined using ∼3 years of data from the ACE spacecraft. No preselection of coronal mass ejections (CMEs) or magnetic clouds is carried out. The correlation between the field intensity and maximum speed is shown to increase significantly when |B| > 18 nT for 3 hours or more. Of the 24 events satisfying this criterion, 50% are magnetic clouds, the remaining half having no ordered field structure. A weaker correlation also exists between southward magnetic field and speed. Sixteen of the events are associated with halo CMEs leaving the Sun 2 to 4 days prior to the leading edge of the events arriving at ACE. Events selected by speed thresholds show no significant correlation, suggesting different relations between field intensity and speed for fast solar wind streams and ICMEs.

Published 10 May 2002.

Index Terms: 2111 Interplanetary Physics: Ejecta, driver gases, and magnetic clouds; 2134 Interplanetary Physics: Interplanetary magnetic fields; 7513 Solar Physics, Astrophysics, and Astronomy: Coronal mass ejections.

Read Full Article (file size: 213146 bytes)    Cited by

Citation: Owens, M. J., and P. J. Cargill (2002), Correlation of magnetic field intensities and solar wind speeds of events observed by ACE, J. Geophys. Res., 107(A5), 1050, doi:10.1029/2001JA000238.