Coronal Mass Ejection: Initiation, Magnetic Helicity, and Flux Ropes. I. Boundary Motion-driven Evolution

The purpose of this paper is to explore the observed physical characteristics of the solar corona streamer belt from 1996 June 1 to August 5. The UV spectral data was collected by the Ultraviolet Coronagraph Spectrometer (UVCS) instrument on board the Solar and Heliospheric Observatory (SOHO) spacecraft. From this data the abundances of oxygen, silicon, and magnesium were determined on an almost daily basis during this time period at both the west and east limbs. The streamer belt was composed of both active and quiescent streamers, which allows for the comparison of these two categories of magnetic field structures. The depletion of these three elemental abundances in the core of quiescent streamers was found, as in previous observations. The variance in abundance with solar rotation was investigated as a consequence of the long time frame considered here. The first ionization potential (FIP) effect was present in the data, and the danger of exploring this phenomena by the traditional FIP bias was also covered. A comparison with in situ elemental abundance data from the Charge, Element, and Isotope Analysis System (CELIAS) instrument on SOHO provides evidence suggesting that active-region streamers and the outer "leg" structural component of quiescent streamers are definite contributors to the slow solar wind.