IRIS observations of chromospheric heating by acoustic waves in solar quiet and active regions

Aims. To study the heating of solar chromospheric magnetic and nonmagnetic regions by acoustic magnetoacoustic waves, deposited acoustic-energy flux derived from observations strong lines is compared with total integrated radiative losses. Methods. A set 23 quiet-Sun weak-plage were observed in Mg II k h Interface Region Imaging Spectrograph (IRIS). The was Doppler velocities at two different geometrical heights corresponding to middle upper chromosphere. scaled nonlocal thermodynamic equilibrium 1D hydrostatic semi-empirical models – obtained fitting synthetic line profiles applied compute characteristics waves studied means a wavelet analysis. Results. Observed propagate upward supersonic speed. In quiet chromosphere, sufficient balance losses maintain temperatures layers under study. active-region comparison shows that contribution only 10−30%. Conclusions. Acoustic play an important role heating, depositing main part their energy compensate for substantial fraction regions. active regions, too small chromosphere has be heated other mechanisms.