Transition region dynamical components

TitreTransition region dynamical components
Type de publicationConference Paper
Year of Publication2002
AuteursR. Hadj, Ben El, Gabriel A. H., and Bely-Dubau F.
ÉditeurSawaya-Lacoste, H.
Conference NameSOLMAG 2002. Proceedings of the Magnetic Coupling of the Solar Atmosphere Euroconference
Date PublishedOct
Résumé

Certain coronal heating theories (e.g. Axford and McKenzie, 1993) propose that small loops of new magnetic fields are born in cell centers of supergranulation. They are carried by convection to the network where they reconnect with network field. We are looking for the observational evidence of this phenomenon. Firstly, we use the differential emission measure (DEM) to identify the plasma associated to these loops. For the first part of this analysis, we develop a numerical technique, using CHIANTI spectroscopic database, to calculate the DEM for given observed spectral intensities obtained by CDS. The method requires an initial input model that is folded through spectral line emissivities. This produces a set of predicted intensities that are then compared with observed values. The DEM is then adjusted iteratively to improve agreement between the observed and predicted intensities. The question which remains, is that of the treatment of the cells alone by separating them from the network. Indeed, cells and network have different properties and should be treated separately. Cell-Network separation is done using image analysis which avoids the errors produced by the histogram method. We measure DEM in cells and network to be able to deduce the loop emissions.