How accurately can we determine the coronal heating mechanism in the large-scale solar corona?

In recent papers by Priest et al., the nature of the coronal heating mechan ism in the large-scale solar corona was considered. The authors compared ob servations of the temperature profile along large coronal loops with simple theoretical models and found that uniform heating along the loop gave the best fit to the observed data. This then led them to speculate that turbule nt reconnection is a likely method to heat the large-scale solar corona. He re we reconsider their data and their suggestion about the nature of the co ronal heating mechanism. Two distinct models are compared with the observat ions of temperature profiles. This is done to determine the most likely for m of heating under different theoretical constraints. From this, more accur ate judgments on the nature of the coronal heating mechanism are made. It i s found that, due to the size of the error estimates in the observed temper atures, it is extremely difficult to distinguish between some of the differ ent heat forms. In the initial comparison the limited range of observed tem peratures (T > 1.5 MK) in the data sets suggests that heat deposited in the upper portions of the loop, fits the data more accurately than heat deposi ted in the lower portions. However if a fuller model temperature range (T < 1.0 MK) is used results in contridiction to this are found. In light of th is several improvements are required from the observations in order to prod uce theoretically meaningful results. This gives serious bounds on the accu racy of the observations of the large-scale solar corona in future satellit e missions such a Solar-B or Stereo.