Search Publications
Solar and interplanetary sources of major geomagnetic storms (Dst <= -100 nT) during 1996-2005
Thompson, B. J.; Webb, D. F.; Zhukov, A. N. +9 more
We present the results of an investigation of the sequence of events from the Sun to the Earth that ultimately led to the 88 major geomagnetic storms (defined by minimum Dst ≤ -100 nT) that occurred during 1996-2005. The results are achieved through cooperative efforts that originated at the Living with a Star (LWS) Coordinated Data-Analysis Works…
Geoeffectiveness of halo coronal mass ejections
Gopalswamy, N.; Yashiro, S.; Akiyama, S.
We studied the geoeffectiveness, speed, solar source, and flare association of a set of 378 halo coronal mass ejections (CMEs) of cycle 23 (1996-2005, inclusive). We compiled the minimum Dst values occurring within 1-5 days after the CME onset. We compared the distributions of such Dst values for the following subsets of halo CMEs: disk halos (wit…
V arc interplanetary coronal mass ejections observed with the Solar Mass Ejection Imager
Webb, D. F.; Kahler, S. W.
Since February 2003, the Solar Mass Ejection Imager (SMEI) has been observing interplanetary coronal mass ejections (ICMEs) at solar elongation angles $\epsilon$ > 20°. The ICMEs generally appear as loops or arcs in the sky, but five show distinct outward concave shapes that we call V arcs. We expect to observe some V arcs, formed by trailing e…
Three-dimensional global simulation of interplanetary coronal mass ejection propagation from the Sun to the heliosphere: Solar event of 12 May 1997
Wu, S. T.; Dryer, M.; Fry, C. D. +2 more
A newly developed hybrid code, HAFv.2+3DMHD, that combines two simulation codes, Hakamada-Akasofu-Fry code version 2 (HAFv.2) and a fully three-dimensional (3-D), time-dependent MHD simulation code, is used to study the global interplanetary coronal mass ejection (ICME) from the 12 May 1997 solar event. The solar wind structure is first simulated …
Prediction of the 1-AU arrival times of CME-associated interplanetary shocks: Evaluation of an empirical interplanetary shock propagation model
Cho, K. -S.; Kim, K. -H.; Moon, Y. -J.
The traveltimes of interplanetary (IP) shocks at 1 AU associated with coronal mass ejections (CMEs) can be predicted by the empirical shock arrival (ESA) model of Gopalswamy et al. [2004] based on a constant IP acceleration. We evaluate the ESA model using 91 IP shocks identified from sudden commencement (SC)/sudden impulse (SI) on the Earth and b…
Two-dimensional hybrid model of wave and beam heating of multi-ion solar wind plasma
ViñAs, A. F.; Ofman, L.
We study the heating and the acceleration of protons and heavy ions by waves in the solar wind, as well as the nonlinear influence of heavy ions on the wave structure, using a two-dimensional (2-D) hybrid model. Protons and heavy ions are treated kinetically by solving their equations of motion in the self-consistent electric and magnetic fields o…
Interaction between coronal mass ejections and the solar wind
Breen, A. R.; Bisi, M. M.; Fallows, R. A. +3 more
Observations suggest that the interplanetary extensions of coronal mass ejections (iCMEs) may be accelerated or decelerated in their passage through the solar wind. Interplanetary scintillation measurements (IPS) can detect the passage of iCMEs beyond the field of view of the Large-Angle and Spectrometric Coronagraph coronagraphs and can provide i…
Large-scale structure of the fast solar wind
Breen, A. R.; Bisi, M. M.; Fallows, R. A. +2 more
We present the results of a comprehensive study of the fast solar wind near solar minimum conditions using interplanetary scintillation (IPS) data taken with the EISCAT system in northern Scandinavia, and a recent extremely long baseline observation using both EISCAT and MERLIN systems. The results from IPS observations suggest that the fast wind …
Constraining and validating the Oct/Nov 2003 X-class EUV flare enhancements with observations of FUV dayglow and E-region electron densities
Meier, R. R.; Lean, J. L.; Paxton, L. J. +10 more
Near peak activity of two X-class solar flares, on 28 October and 4 November 2003, the Thermosphere Ionosphere Mesosphere Energetics and Dynamics (TIMED)/Solar EUV Experiment (SEE) instrument recorded order of magnitude increases in solar EUV irradiance, the TIMED/Global Ultraviolet Imager (GUVI) observed simultaneous increases in upper atmosphere…
Radio tracking of the interplanetary coronal mass ejection driven shock crossed by Ulysses on 10 May 2001
MacDowall, R. J.; Hoang, S.; Lacombe, C. +1 more
We report on the detection of type II radio emission which was observed for more than a day prior to the arrival of an interplanetary shock at Ulysses. We use local spectral emission peaks, computerized from time-averaged intensity spectra of the type II burst, to track the associated emitting shock. In the spectrogram plotted as a function of tim…