Properties of the prominence magnetic field and plasma distributions as obtained from 3D whole-prominence fine structure modeling

Abstract

Aims. We analyze distributions of the magnetic field strength and prominence plasma (temperature, pressure, plasma β, and mass) using the 3D whole-prominence fine structure model. Methods. The model combines a 3D magnetic field configuration of an entire prominence, obtained from non-linear force-free field simulations, with a detailed semi-empirically derived description of the prominence plasma. The plasma is located in magnetic dips in hydrostatic equilibrium and is distributed along multiple fine structures within the 3D magnetic model. Results. We show that in the modeled prominence, the variations of the magnetic field strength and its orientation are insignificant on scales comparable to the smallest dimensions of the observed prominence fine structures. We also show the ability of the 3D whole-prominence fine structure model to reveal the distribution of the prominence plasma with respect to its temperature within the prominence volume. This provides new insights into the composition of the prominence-corona transition region. We further demonstrate that the values of the plasma β are small throughout the majority of the modeled prominences when realistic photospheric magnetic flux distributions and prominence plasma parameters are assumed. While this is generally true, we also find that in the region with the deepest magnetic dips, the plasma β may increase towards unity. Finally, we show that the mass of the modeled prominence plasma is in good agreement with the mass of observed non-eruptive prominences.

Manifestations of Three-dimensional Magnetic Reconnection in an Eruption of a Quiescent Filament: Filament Strands Turning to Flare Loops

“…Numerical models revealed that filaments are located in magnetic dips within large flux ropes composed of twisted field lines (see e.g. Aulanier & Schmieder 2002;Dudík et al 2008;Gunár & Mackay 2016).…”

Large-amplitude Longitudinal Oscillations Triggered by the Merging of Two Solar Filaments: Observations and Magnetic Field Analysis

“…They have been intensively observed and studied since the 19th century (see e.g., E. Tandberg-Hanssen 1995; Labrosse et al 2010;Mackay et al 2010). It is believed today that the cool dense plasma of prominences is suspended in magnetic flux ropes or sheared arcades due to the upward magnetic tension of the magnetic field (Aulanier et al 1998;Gunar et al 2013;Gunar & Mackay 2016). Observations reveal that even so-called "quiescent" prominences are highly dynamic, consisting of flowing plasma (Zirker et al 1994(Zirker et al , 1998Schmieder et al 2014), plumes, bubbles (Berger et al 2008;Berger et al 2010;Dudík et al 2012;Heinzel et al 2008;Gunar et al 2014) and ubiquitous oscillations and waves (see e.g., Okamoto et al 2007;Schmieder et al 2013;Arregui et al 2012).…”

Diagnostic potential of the Ca II 8542 Å line for solar filaments

“…3.4). This gives us a maximum value for the magnetic field strength of the order of B 2 + B 2 ⊥ ∼260 G, a result still quite high compared to the values found in the literature (Gunár & Mackay 2016).…”