On the structure of the upper atmosphere of Capella.

The emission measures of layers with temperatures of from about 10,000 to about 10 million K are determined for the star Alpha Aur Ab (F9 III) from the entire collection of X-ray, ultraviolet, and optical data. The height distribution of the temperature is derived from these data under the assumption that the pressure is approximately constant in the transition region. The extent of the layers with T = about 20,000-200,000 K is about 1000 km, which considerably exceeds the corresponding theoretical value coming from the assumption that the transition region is formed by a downward heat flux from the corona, as occurs on the sun. Coronal layers are also included in the model constructed. The extent of the transition region of Alpha Aur Ab is consistent with the observed descending motions, possibly connected with the condensation of coronal gas and its descent.