IUE observations of high galactic latitude F supergiants HD 161796 and HD 187885

Abstract

Low resolution (6 A) IUE ultraviolet spectra of the high galactic latitude F supergiants HD 161796 (F3 Ib) and HD 187885 (F2-3I) are analyzed. The UV spectrum (1250 A to 3250 A) of HD 161796 shows no excess UV flux attributable to a hot degenerate companion. From the UV spectrum the temperature is found to be 6300 K. There is no evidence for significant metal deficiency. Except for the semiforbidden N IV 1487 A line the rest of the transition region emission lines are weak. In spite of the large IR (IRAS) excess, the 2200 A region shows no evidence for circumstellar reddening. The UV spectrum (1250 A to 1900 A) of HD 187885 is peculiar. A broad emission feature with emission peak centered around 1580 A is present. A broad absorption feature nearly 100 A wide centered around 1657 A appears to be present. This absorption feature may be due to C I or due to quasi-molecular absorption of the H2.