ANOMALOUS DIFFUSE FEATURES IN DUST-EMBEDDED STARS

We present the results of a study of the λλ 5780, 5797 diffuse interstellar features in 21 early-type stars. Anomalously weak equivalent widths with respect to interstellar reddening are found for several stars associated with regions of current or recent star formation in Orion, Perseus and the Pleiades. There are indications in the results that the individual diffuse bands and the λ 2200 extinction feature may not correlate precisely with each other in sight-lines where anomalies occur. A comparison of HD 24534 (χ Per) with other stars in Perseus and with stars in CMa R1 suggests that cloud density may be the critical factor in determining the diffuse band production efficiency. © 1983 Royal Astronomical Society.