Steady Flow Model of a Magnetic Flux Tube Constrained to Observed Differential Emission Measure

Abstract

We have investigated one dimensional steady flow model of a typical magnetic flux tube in the solar transition region constrained to observed Differential Emission Measure (DEM) for the average quiet-Sun deduced by Raymond & Doyle (1981) with a flux tube geometry conforming to Doppler shifts of UV lines measured by Chae, Yun & Poland (1998). Because local heating and filling factor in the transition region are not well known, we considered two extreme cases, one characterized by the filling factor = 1 ("filled-up model") and the other set by local heating = 0 ("not-heated model"). We examined how much the heating is required for the flux tube by recomputing a model through adjustment of the filling factor in such a way that "not-heated model" accounts for the observed DEM.