The 1 October 2001 Eruptive Prominence: Observed and Modeled Structures

Using TRACE 171 Å image observations and Hα spectra and images observed at the Ondrejov Observatory, the October 1, 2001, eruptive prominence is studied. The evolution of this prominence is described and velocities of specific parts of the prominence are determined. It was found that, after the rising phase of the cold loop-like prominence, its upper part expanded and below this expanding part, around one of its legs a `ring' structure, visible in the TRACE images, was formed. Then, at the same place, a tearing of the prominence leg was recognized. Simultaneous spectral observations of this structure reveal a very broad Hα line, which indicates strong turbulent motion at these positions. These processes were accompanied by an expanding Hα envelope. Due to the similarity of the observed `ring' and tearing structures with those modeled by Lau and Finn (1996), the prominence leg tearing is interpreted as a reconnection process between two parallel magnetic ropes having parallel electric currents, but anti-parallel axial magnetic fields.[PUBLICATION ABSTRACT]