Two-component model of solar plages

By use of the 2-m Mcmath-Pierce telescope at Kitt Peak, the high-quality spectra of aplage with moderate brightness near the center of solar disk were obtained. The data includeseven spectral lines, which are Hα, Hβ, Call H and K lines and the infrared triplet. With the con-sideration of fine structures of solar plages, a two-component atmospheric model is constructed by keeping the cool component to be the quiet atmosphere. Three cases of the hot component aregiven for different filling factors where the temperature and density distribution are adjusted in or-der to reproduce the seven observed spectral profiles. We also briefly discuss the influence of thecolumn density at the base of the corona, m, and the macro-turbulent velocity on the required filling factor and computed profiles. The two-component model is compared with precious one-component semi-empirical models. The limitation of the model is pointed out and further im-provement is indicated.