Medium resolution EUV observations and network structure

Medium resolution observations have been used to find the fractional emitting area in three transition region lines. It is found that is given by DI _{mg x} ^k where k varies from 0.78 to 0.51 in the temperature range 2 × 10⁵ to 7 × 10⁵ K. The average emitting area in O vi deduced by this method is in good agreement with the results from ATM observations. The fractional emitting areas at different values of the Mg x intensity and at different temperatures are combined to find the variation of the areas with height. This variation is in good agreement with Giovanelli's model of the fractional area of cross-section of a magnetic tube of force in the transition region.