Statistical Distributions of Speeds of Coronal Mass Ejections

We studied the distribution of plane-of-sky speeds determined for 4315 coronal mass ejections (CMEs) detected by the Large Angle and Spectrometric Coronagraph Experiment on board the Solar and Heliospheric Observatory (SOHO LASCO). We found that the speed distributions for accelerating and decelerating events are nearly identical and to a good approximation they can be fitted with a single lognormal distribution. This finding implies that, statistically, there is no physical distinction between the accelerating and the decelerating events. The lognormal distribution of the CME speeds suggests that the same driving mechanism of a nonlinear nature is acting in both slow and fast dynamical types of CMEs.

[1]  R. Howard,et al.  Continuous tracking of coronal outflows : Two kinds of coronal mass ejections , 1999 .

[2]  N. Gopalswamy,et al.  Characteristics of coronal mass ejections associated with long-wavelength type II radio bursts , 2001 .

[3]  Philip R. Goode,et al.  Signature of an Avalanche in Solar Flares as Measured by Photospheric Magnetic Fields , 2003 .

[4]  N. Gopalswamy,et al.  Interplanetary acceleration of coronal mass ejections , 2000 .

[5]  E. Lu,et al.  Avalanches and the Distribution of Solar Flares , 1991 .

[6]  Paul Charbonneau,et al.  Avalanche models for solar flares (Invited Review) , 2001 .

[7]  S. Suess,et al.  JD 7: The Sun and the Heliosphere as an Integrated System , 2004 .

[8]  N. Gopalswamy.  A Global Picture of CMEs in the Inner Heliosphere , 2004 .

[9]  G. Aulanier,et al.  Interpretation of a complex CME event: Coupling of scales in multiple flux systems , 2003 .

[10]  Bojan Vršnak,et al.  Influence of the aerodynamic drag on the motion of interplanetary ejecta , 2002 .

[11]  Russell A. Howard,et al.  Properties of coronal mass ejections: SOHO LASCO observations from January 1996 to June 1998 , 2000 .

[12]  Haimin Wang,et al.  A Statistical Study of Two Classes of Coronal Mass Ejections , 2002 .

[13]  Jacques Verron,et al.  Can we improve the representation of modeled ocean mixed layer by assimilating surface-only satellite-derived data? A case study for the tropical Pacific during the 1997-1998 El Nino , 2003 .

[14]  B. Vršnak.  Eruptive instability of cylindrical prominences , 1990 .

[15]  Haimin Wang,et al.  High-Cadence Observations of an Impulsive Flare , 2000 .

[16]  I. Lerche,et al.  Distribution of sunspot umbral areas - 1917-1982 , 1988 .

[17]  E. Hildner,et al.  The speeds of coronal mass ejection events , 1976 .

[18]  James Chen,et al.  Acceleration of coronal mass ejections , 2002 .

[19]  Haimin Wang,et al.  Observations of Nonthermal and Thermal Hard X-Ray Spikes in an M-Class Flare , 2004 .

[20]  N. Ograpishvili.  Distribution of active regions on the solar surface estimated by statistical methods , 1994 .

[21]  N. Gopalswamy,et al.  A catalog of white light coronal mass ejections observed by the SOHO spacecraft , 2004 .

[22]  James Chen.  Theory of prominence eruption and propagation: Interplanetary consequences , 1996 .

[23]  R. MacQueen,et al.  The kinematics of solar inner coronal transients , 1983 .

[24]  B. Low,et al.  The Hydromagnetic Origin of the Two Dynamical Types of Solar Coronal Mass Ejections , 2001 .