Modeling the Effect of Mass-draining on Prominence Eruptions

Abstract

Quiescent solar prominences are observed to exist within the solar atmosphere for up to several solar rotations. Their eruption is commonly preceded by a slow increase in height that can last from hours to days. This increase in the prominence height is believed to be due to their host magnetic flux rope transitioning through a series of neighbouring quasi-equilibria before the main loss-of-equilibrium that drives the eruption. Recent work suggests that the removal of prominence mass from a stable, quiescent flux rope is one possible cause for this change in height. However, these conclusions are drawn from observations and are subject to interpretation. Here we present a simple model to quantify the effect of "mass-draining" during the pre-eruptive height-evolution of a solar flux rope. The flux rope is modeled as a line current suspended within a background potential magnetic field. We first show that the inclusion of mass, up to 10 12 kg, can modify the height at which the line current experiences loss-of-equilibrium by up to 14%. Next, we show that the rapid removal of mass prior to the loss-of-equilibrium can allow the height of the flux rope to increase sharply and without upper bound as it approaches its loss-of-equilibrium point. This indicates that the critical height for the loss-of-equilibrium can occur at a range of heights depending explicitly on the amount and evolution of mass within the flux rope. Finally, we demonstrate that for the same amount of drained mass, the effect on the height of the flux rope is up to two order of magnitude larger for quiescent than for active region prominences.

Prominence formation by levitation-condensation at extreme resolutions

“…We see that for the 3G case, the O-point of the flux rope initially oscillates as a result of the formation process before the condensation of the prominence interrupts this bulk oscillation, as indicated with the clear displacement of the O-point to lower heights (cf. Shafranov Shift, Blokland & Keppens 2011a;Jenkins et al 2019). Strikingly, the position of O-point and prominence material in time appear completely correlated between 2800 t 4500 s before the initiation of the internal reconnection that allows both the prominence material to continue falling and the O-point to return to a height of ≈ 15 Mm (an evolution that may prove related/comparable to eruptions that involve the ejection of a flux rope but leave the prominence behind e.g., Gilbert et al 2001;Jenkins et al 2018).…”

Magnetic Structure of an Erupting Filament

“…The amplitudes of such dynamics are also significantly larger than those at the smaller scales, with velocities and displacements in the region of 30 -100 km s −1 and 110 Mm, respectively (e.g., Luna & Karpen 2012;Luna et al 2014;Liakh et al 2020). More recently, similarly large-scale and correlated mass motions occurring in the lead-up to a filament eruption have been added to the conditions for global flux rope stability (e.g., Bi et al 2014;Reva et al 2017;Jenkins et al 2018Jenkins et al , 2019Fan 2020), alongside the more commonly-considered stability conditions (e.g., torus/kink instability, breakout reconnection, tether cutting, etc. ; Antiochos et al 1999;Moore et al 2001;Török & Kliem 2005;Kliem & Török 2006).…”

A new trigger mechanism for coronal mass ejections

“…The heights place the ropes in the β < 1 region of the solar atmosphere (see Fig. 3 of Gary 2001), implying that plasma does not contribute to the stability of these HFT flux ropes in the same way that it would if their undersides were line-tied to dense photospheric or chromospheric plasma in a BPS configuration or if they contained dense filament plasma (Jenkins et al 2018(Jenkins et al , 2019. If perturbed, reconnection could occur at the HFT under these flux ropes, aiding the eruption of the structure.…”