Determinación de propiedades morfológicas de arcos coronales

M. C. LÓPEZ FUENTES; P. DÉMOULIN; J. A. KLIMCHUK

Mérida, México

Conferencia; VIII Conferencia Latinoamericana de Geofísica Espacial; 2007

Asociación Latinoamericana de Geofísica Espacial

We study the effect of the coronal background in the determination of the diameter of EUVloops, and we analyze the suitability of the procedure followed in a previous paper (LopezFuentes, Klimchuk & Demoulin 2006) for characterizing their expansion properties. For theanalysis we create different synthetic loops and we place them on real backgrounds from data obtained with the Transition Region and Coronal Explorer (TRACE). We apply to these loops the same procedure followed in our previous works, and we compare the results with real loop observations. We demonstrate that the procedure allows us to distinguish constant width loops from loops that expand appreciably with height, as predicted by simple force-free field models. This holds even for loops near the resolution limit. We find no statistical correlation between variations of the measured width and of the background. Therefore, we confirm that the background does not significantly influence the determination of the overall expansion properties of loops.