An interesting episode of accretion activity in UX orionis

This paper presents observations of an episode of accretion activity in the pre-main-sequence star UX Ori. High-velocity, redshifted absorption is see n in several lines of H, Ca II, Na I, and Fe II during an interval of eight nights in the fall of 1996 with similar velocity and time evolution. A non -LTE analysis of the line optical depths shows that the infalling gas canno t be heavily hydrogen-depleted, as would be expected if it was produced by the evaporation of a solid body of chemical composition similar to solar sy stem comets. On the contrary, the observations are consistent with gas of s olar chemical composition at temperature similar to 6000-7000 K.