Tracking Filament Evolution in the Low Solar Corona using Remote-Sensing and In-situ Observations

TL;DR

This study tracks filament eruption dynamics in the low solar corona using remote sensing and in-situ data, revealing plasma heating, heterogeneity, and ionization states during the eruption.

Contribution

It introduces a novel absorption diagnostic technique and combines multi-instrument observations to analyze filament plasma evolution in unprecedented detail.

Findings

Filament plasma was in near ionization equilibrium.

Filament material was continuously heated during expansion.

Filament plasma was heterogeneous in composition.

Abstract

In the present work, we analyze a filament eruption associated with an ICME that arrived at L1 on August 5th, 2011. In multi-wavelength SDO/AIA images, three plasma parcels within the filament were tracked at high-cadence along the solar corona. A novel absorption diagnostic technique was applied to the filament material travelling along the three chosen trajectories to compute the column density and temperature evolution in time. Kinematics of the filamentary material were estimated using STEREO/EUVI and STEREO/COR1 observations. The Michigan Ionization Code used inputs of these density, temperature, and speed profiles for the computation of ionization profiles of the filament plasma. Based on these measurements we conclude the core plasma was in near ionization equilibrium, and the ionization states were not frozen-in at the altitudes where they were visible in absorption in AIA images. Additionally, we report that the filament plasma was heterogeneous, and the filamentary material was continuously heated as it expanded in the low solar corona.