Analysis and interpretation of a fast limb CME with eruptive prominence, C-flare and EUV dimming

TL;DR

This study analyzes a fast limb CME event from December 2003 using multi-wavelength observations to understand its origin, dynamics, and magnetic structure, revealing a significant mass ejection and associated flare activity.

Contribution

It provides a comprehensive multi-instrument analysis of a fast limb CME, combining ground-based and space-borne data to investigate its magnetic structure and mass dynamics.

Findings

CME mass exceeds prominence mass, indicating additional mass sources.

Eruptive prominence observed with high cadence H-alpha imaging.

Coronal dimming of 5% in EUV channels associated with CME.

Abstract

Coronal Mass ejections or CMEs are large dynamical solar-corona events. The mass balance and kinematics of a fast limb CME, including its prominence progenitor and the associated flare, will be compared with computed magnetic structures to look for their origin and effect. Multi-wavelength ground-based and space-borne observations are used to study a fast W-limb CME event of December 2, 2003, taking into account both on and off disk observations. Its erupting prominence is measured at high cadence with the Pic du Midi full H-alpha line-flux imaging coronagraph. EUV images from space instruments are processed including difference imaging. SOHO/LASCO images are used to study the mass excess and motions. A fast bright expanding coronal loop is identified in the region recorded slightly later by GOES as a C7.2 flare, followed by a brightening and an acceleration phase of the erupting material with both cool and hot components. The total coronal radiative flux dropped by 5 percent in the EUV channels, revealing a large dimming effect at and above the limb. The typical 3-part structure observed 1 hour later shows a core shaped similarly to the eruptive filament/prominence. The total measured mass of the escaping CME (1.5x10to16 g from C2 LASCO observations) definitely exceeds the estimated mass of the escaping cool prominence material although assumptions made to analyse the Ha erupting prominence, as well as the corresponding EUV darkening of the filament observed several days before, made this evaluation uncertain by a factor of 2. From the current free extrapolation we discuss the shape of the magnetic neutral surface and a possible scenario leading to an instability, including the small scale dynamics inside and around the filament.