Laboratory Simulation of Arched Magnetic Flux Rope Eruptions in the Solar Atmosphere

Dramatic eruption of an arched magnetic flux rope in a large ambient plasma has been studied in a laboratory experiment that simulates coronal loops. The eruption is initiated by laser generated plasma flows from the footpoints of the rope that significantly modify the magnetic-field topology and link the magnetic-field lines of the rope with the ambient plasma. Following this event, the flux rope erupts by releasing its plasma into the background. The resulting impulse excites intense magnetosonic waves that transfer energy to the ambient plasma and subsequently decay.

Figure 1

(a) Schematic of the experiment showing the AMFR, laser beams, vacuum magnetic fields, and $xyz$ coordinate system. The origin of the coordinate system is located on the machine axis (dotted line) where both laser beams intersect. The AMFR moves through the origin as it evolves. (b) Side ($xy$) and front ($yz$) views of the rectangular measurement plane and AMFR [shaded (pink) region].

Figure 2

(a) Image of a stable AMFR. Laser generated plasma jets are shown by arrows and the approximate location of the linkage region is indicated by the dots. (b) Time evolution of the plasma density profile of the AMFR during the eruption is shown at $y=0\mathrm{cm}$ in the $xy$ measurement plane of Fig. 1b. The outward motion (along $-x$ direction of the arrow) of the erupting AMFR is a prominent feature that can be observed in these line plots.

Figure 3

Surface plot $n(x,t)$ covering the eruption and magnetosonic wave propagation time phases of the AMFR. The $V$-shaped phase fronts of the magnetosonic wave are better visualized in the inset. The light (yellow) and dark (blue) regions show the crest and trough of the wave, respectively.

Figure 4

Time evolution of the magnetic-field vectors of the AMFR displayed in the measurement plane of Fig. 1b at $z=-5\mathrm{cm}$ after the laser trigger at $t=0\mu \mathrm{s}$. Panel (a) shows 2D projection of the AMFR magnetic field. The $B_z$ component is suppressed. Panel (b) shows 3D magnetic field in a perspective view of the measurement plane.