Chromospheric and coronal heating

From computations for a theoretical model chromosphere matched to the empirical model of Vernazza, Avrett, and Loeser published in 1981, it is concluded that the required magnitude and mass dependence of the heat input are compatible with heating by sound waves whose velocity amplitude is near the sound speed. However, the required rate of heat input per gram increases markedly at the top of the neutral chromosphere, and a different form of heating appears necessary in the corona and transition region. 24 references