List of Figures

View Image Figure 1:
White-light images of two types of typical CMEs (from SOHO/LASCO database). (a) A narrow CME on 1997 March 11, where the 195 Å disk image is overplotted on the occulting disk; (b) a normal CME on 2000 February 27 with a three-part structure, i.e., a frontal loop, a cavity, and a bright core, where the white circle marks the solar limb.
View Image Figure 2:
The CME daily occurrence rate detected by the CACTus archive (red) and the CDAW archive (blue) compared with the daily sunspot number (gray) during solar cycle 23. Thin curves: smoothed per month, thick curves: smoothed over 13 months (from Robbrecht et al., 2009).
View Image Figure 3:
Schematic models to describe the eruption of narrow CMEs (left) and normal CMEs (right). The right panel is taken from Forbes (2000).
View Image Figure 4:
The flux rope model for the CME progenitor, where the shaded area corresponds to the dome of a helmet streamer surrounding a cavity in the middle, and a prominence is located at the bottom of the flux rope. Note that the self-closed flux rope is the projection of a 3D helical flux rope (from Low and Hundhausen, 1995).
View Image Figure 5:
Nonlinear force-free coronal magnetic field lines (white lines) overplotted on the photospheric magnetogram (gray) on 2000 July 14. The horizontal and vertical axes are in unit of arcsec. (from Yan et al., 2001).
View Image Figure 6:
Schematic sketch of two types of the pre-CME magnetic structures. (a) The core field has an inverse polarity at its dips; (b) the core field has a normal polarity at its center, where there may or may not exist dips.
View Image Figure 7:
Two examples showing new magnetic flux emerging inside the filament channel (left, the 1992 February 23 event) and outside the filament channel (right, the 1998 February 23 event) (from Chen and Shibata, 2000).
View Image Figure 8:
Soft X-ray light curve just prior to a big flare. An SXR enhancement, visible ∼ 20 min before the main flare, is associated with the eruption of a filament (adapted from Simnett and Harrison, 1985).
View Image Figure 9:
164 MHz radio noise storm (contour) overplotted on the EIT base difference map (gray) showing the dimming region associated with the CME on 2000 July 14 (from Wen et al., 2007).
View Image Figure 10:
The number of type III radio bursts per hour (histogram) that were observed around the first appearance of the CME (double-ended arrow). Note that the occurrence rate is averaged every 5 hours, and the dashed line marks the average rate of type III bursts over years (from Jackson et al., 1978).
View Image Figure 11:
EIT base difference images showing the filament darkening and widening before eruption (from Klassen et al., 2002).
View Image Figure 12:
Panel (a): evolution of the Dopplergram along the SUMER slit observed at S iii/Si iii 1113 Å showing prominence oscillations before eruption, where the Doppler velocity is in unit of km s–1. Panels (b-c): new magnetic flux emerges near a filament channel, and reconnects with the pre-existing magnetic field. The localized reconnection drives the prominence oscillation before final eruption (from Chen et al., 2008).
View Image Figure 13:
The tether-cutting triggering mechanism for CMEs. Left: strongly sheared core field is restrained by the overlying less-sheared envelope field; Middle: The reconnection between field lines AB and CD triggers the core field to rise; Right: The rising core field stretches up the envelope field, forming a current sheet below the core field (adapted from Moore et al., 2001).
View Image Figure 14:
Flux cancellation in a strongly sheared magnetic arcade leading to the formation and levitation of a flux rope. Further cancellation leads to the eruption of the flux rope (from van Ballegooijen and Martens, 1989).
View Image Figure 15:
The evolution of the magnetic field in the breakout model, showing the reconnection above the central flux system removes the constraint over the core field (thick lines), and results in the final eruption (adapted from Antiochos et al., 1999).
View Image Figure 16:
Schematic diagram of the emerging flux triggering mechanism for CMEs. (a) Emerging flux inside the filament channel cancels the pre-existing loops, which results in the in-situ decrease of the magnetic pressure. Lateral magnetized plasmas are driven convergently to form a current sheet; (b) Emerging flux outside the filament channel reconnects with the large coronal loop, which results in the expansion of the loop. The underlying flux rope then rises and a current sheet forms near the magnetic null point (from Chen, 2008).
Watch/download Movie Figure 17: (gif-Movie; 776 KB)
Movie: Evolutions of the magnetic field (lines), temperature (color, in unit of 106 K), and velocity (arrows) in the corona after the flux rope system is triggered to rise when the new flux emerges inside the filament channel (from Chen and Shibata, 2000).
Watch/download Movie Figure 18: (gif-Movie; 776 KB)
Movie: Evolutions of the magnetic field (lines), temperature (color, in unit of 106 K), and velocity (arrows) in the corona after the flux rope system is triggered to rise when the new flux emerges outside the filament channel (from Chen and Shibata, 2000).
View Image Figure 19:
(a) Schematic drawing of the flux injection triggering mechanism for CMEs, where Bp denotes the poloidal magnetic field of a flux rope; A, B, and C mark the apex, the centroid, and the bottom of the flux rope, respectively. A prominence is supposed to sit at the bottom of the flux rope; (b) Time evolution of the velocity of the flux rope apex as a certain amount of poloidal flux is injected into the rope (adapted from Chen, 1996).
View Image Figure 20:
The evolution of the kink instability of a twisted flux tube based on an analytical solution (from Sakurai, 1976).
View Image Figure 21:
Top: the MHD simulation of the kink instability of a strongly-twisted flux tube emerging from the subsurface to the corona, where the pre-existing magnetic field declines slowly with height. Bottom: the MHD simulation of the torus instability of a weakly-twisted flux tube emerging into the corona, where the pre-existing magnetic field declines rapidly with height (adapted from Fan and Gibson, 2007).
View Image Figure 22:
Variation of the equilibrium state of a flux rope system as the amount of the cancelling flux (ϕ) increases. From panel (e) to panel (f), a catastrophe takes place (from Forbes and Isenberg, 1991).
View Image Figure 23:
The magnetic evolution showing that the flux rope jumps from an initial equilibrium state (t = 30 τ A) to a higher state (t = 180τ A) when the magnetic shear reaches a critical value (from Hu, 2001).
View Image Figure 24:
The evolution of the magnetic field in the 3D MHD numerical simulation of Amari et al. (2000), which shows the formation and the ensuing eruption of a twisted flux rope as a simple magnetic arcade experiences shearing motions and the opposite-polarity magnetic emergence (adapted from Amari et al., 2000).
View Image Figure 25:
Schematic sketch showing that the reconnection inflow in one CME eruption induces the loss of equilibrium of a neighboring filament (from Cheng et al., 2005).
View Image Figure 26:
Schematic sketch showing that closed magnetic field is surrounded by an accelerating solar wind background.
View Image Figure 27:
Temporal variations of the plasmoid velocity (V plasmoid, dotted line), its height (solid line), and inflow velocity (Vinflow, dashed line) in the analytical model of Shibata and Tanuma (2001).
View Image Figure 28:
Diagram of the magnetic configuration including an erupting flux rope and a current sheet between the flux rope and the reconnected flare loop used for the setup of the analytical solution by Lin and Forbes (2000).
View Image Figure 29:
Temporal evolutions of the flux rope height (h) and the magnetic reconnection rate (R) in the numerical simulation of Chen and Shibata (2000), which shows that the strong acceleration of the flux rope is coincident with the peak reconnection rate.
View Image Figure 30:
Temporal evolutions of the SXR flux of the flare (solid line) and the propagation velocity of the CME frontal loop (dotted line), showing a three-phase pattern (from Zhang et al., 2001a).
View Image Figure 31:
Schematic sketch showing how a CME frontal loop expands to be asymmetric to the underlying flare in the early stage. The black solid lines correspond to the initial magnetic field, the black dashed lines to the deformed magnetic field, and the green dashed lines to the CME frontal loop formed by the successive stretching of magnetic field lines. The arrows indicate that the flux rope is erupting.
View Image Figure 32:
Schematic sketch showing how a CME expands to a global scale as it pushes up the overlying interconnecting loops. The gray lines corresponds to small-scale magnetic field, black lines to the interconnecting lines (adapted from Delannée and Aulanier, 1999).
View Image Figure 33:
The LASCO/C2 white-light images showing a faint bow shock straddling over the 1999 April 2 CME. The solar disk is revealed by the EIT 195 Å images (adapted from Vourlidas et al., 2003).
View Image Figure 34:
Schematic sketch showing the possible shocks associated with CMEs in the standard model. Besides the piston-driven shocks, another two fast-mode termination shocks, which are formed as reconnection outflows (long blue arrows) collide with the flux rope and the flare loop, are indicated by red bars. Black solid lines correspond to the magnetic field, dashed lines to the slow-mode shock fronts.
View Image Figure 35:
Schematic sketch showing that in the 3D space a twisted flux rope can rupture the overlying magnetic arcade and erupt alone by pushing the magnetic arcade aside (from Sturrock et al., 2001).
View Image Figure 36:
Velocity distributions along the height for some CMEs observed by Skylab satellite (Gosling et al., 1976).
View Image Figure 37:
Phenomenological models for the slow CMEs (top panels) and the fast CMEs (bottom panels), where the filament is supported in an inverse polarity flux rope and a normal polarity flux rope, respectively (from Low and Zhang, 2002).
View Image Figure 38:
EIT 195 Å base difference images showing the evolution of the most famous EIT wave event on 1997 May 12 (from the SOHO/EIT data archive).
View Image Figure 39:
Comparison between the observation of the 1997 May 12 EIT wave event and the 3D MHD simulation of fast-mode waves in the low corona (adapted from Wu et al., 2001).
View Image Figure 40:
Upper panels: The evolutions of the density (color, in unit of 1.67 × 10–12 kg m–3), magnetic field (lines), and velocity field (arrows) as a flux rope is ejected upward. The scale for the velocity is shown at the upper-right corner. Lower panels: the schematic sketch of the fieldline successive stretching model for EIT waves (adapted from Chen et al., 2002).
View Image Figure 41:
The schematic sketch of the successive magnetic reconnection model for EIT waves (from Attrill et al., 2007).
View Image Figure 42:
The evolutions of the magnetic field (lines) and J ⋅ B ∕B2 (isosurfaces) in the MHD simulations of Delannée et al. (2008). The isosurface of J ⋅ B∕B2 indicates a current shell just outside the erupting flux tube (adapted from Delannée et al., 2008).
View Image Figure 43:
The flux rope model for the CME frontal loop (from Mouschovias and Poland, 1978).
View Image Figure 44:
A schematic sketch of the formation mechanism of CME leading loops, where the CME leading loop (green) are apparently-moving density enhanced structure that is generated by the successive stretching of magnetic field lines as the erupting core structure, e.g., a flux rope, continues to push the overlying field lines to expand outward successively. The piston-driven shock is shown as pink lines (from Chen, 2009a).
View Image Figure 45:
A sketch showing how a dome-like CME would be observed as a limb event (green lines) and as a halo event (blue lines). The pink line ahead of the CME is the fast-mode piston-driven shock wave. α is the inclined angle between the radial direction of point F and the plane of the sky, whereas β is the angle between the CME leg and the plane of the sky. It is seen that the far wing, say, near point F, propagates in a direction closer to the plane of the sky than the CME does (since α < β).