ON THE ABSENCE OF A RELATIONSHIP BETWEEN THE PROPERTIES OF THE T-E-GREATER-THAN-OR-EQUAL-TO-10(6) K AND THE PROPERTIES OF THE T-E-LESS-THAN-OR-EQUAL-TO-7X10(5) SOLAR PLASMAS

Traditional solar upper atmosphere models assume continuity along solar upper atmosphere structures, from the T-e greater than or equal to 10(6) K corona to the T-e approximate to 10(4) K chromosphere. Under such conditions a transition region with 3 x 10(4) less than or equal to T-e less than or equal to 1 x 10(6) K should exist between the corona and chromosphere. According to such models, plasma properties of the corona could be inferred from plasma properties of the so-called transition region. Inherent in such models are assumptions that plasmas in such structures (most likely loops) are in hydrostatic equilibrium, and heat is distributed along them by thermal conduction. When accounting for coronal heat losses based on such models three mechanisms are mentioned: (1) radiation by coronal plasma; (2) thermal conductivity between the 10(6) K corona and the 10(4) K chromosphere and (3) mass motions, mostly into the solar wind. According to these models, thermal conductivity is the most efficient among the coronal heat loss mechanisms. In this paper, we describe studies of the relationships between structures having temperatures of T-e greater than or equal to 1 x 10(6) and those with temperatures of T-e < 7 x 10(5) K. We show that effects of thermal conduction between the hot and the cold regions are not seen at the expected levels, impying that unimpaired continuity is not being maintained between the 10(6) and 10(4) K plasma regions. As a consequence of these findings, we stress that no conclusion on the properties of T-e greater than or equal to 1 x 10(6) K plasmas can be drawn from properties of the so-called transition region (3 x 10(4) less than or equal to T-e less than or equal to 7 x 10(5) K) plasmas.