Semi-empirical models of a quiescent prominence

In the paper semi-empirical quiescent prominence models which satisfy the constraints of the radiative transfer equation, hydrostatic and statistical equilibrium are proposed. The atom is assumed to have five levels plus one continuum for hydrogen as well as for ionized calcium. The models reproduce well the observed Hα, Hβ, Ca II H and K line profiles. The results indicate that the temperature from the outer layer to the centre of the prominence decreases and the source functions of Hα, Hβ, Hγ, Ca II H and K lines increase. By computing radiation losses, it is found that the radiative loss due to hydrogen is much larger than that due to ionized calcium.