NUMERICAL SIMULATIONS OF THE MAGNETIC RAYLEIGH-TAYLOR INSTABILITY IN THE KIPPENHAHN-SCHLÜTER PROMINENCE MODEL. II. RECONNECTION-TRIGGERED DOWNFLOWS

Abstract

The launch of the Hinode satellite has allowed unprecedented high resolution, stable images of solar quiescent prominences to be taken over extended periods of time. These new images led to the discovery of dark upflows that propagated from the base of prominences developing highly turbulent profiles. As yet, how these flows are driven is not fully understood. To study the physics behind this phenomena we use 3-D magnetohydrodynamic (MHD) simulations to investigate the nonlinear stability of the Kippenhahn-Shl\"{u}ter prominence model to the magnetic Rayleigh-Taylor instability. The model simulates the rise of a buoyant tube inside a quiescent prominence, where the upper boundary between the tube and prominence model is perturbed to excite the interchange of magnetic field lines. We found upflows of constant velocity (maximum found 6\,km\,s$^{-1}$) and a maximum plume width $\approx 1500$\,km which propagate through a height of approximately 6\,Mm in the no guide field case. The case with the strong guide field (initially $B_y=2B_x$) results in a large plume that rises though the prominence model at $\sim 5$\,km\,s$^{-1}$ with width $\sim 900$\,km (resulting in width of 2400\,km when viewed along the axis of the prominence) reaching a height of $\sim 3.1$\,Mm. In both cases nonlinear processes were important for determining plume dynamics.