Position displacement of diffuse interstellar bands

Abstract

We re-consider the already published phenomenon: the blue shift of diffuse interstellar bands, observed in spectra of HD34078 (AE Aur) and members of the Sco OB1 association, in particular HD152233. We have analyzed 29 diffuse bands. Part of them, already proven as blue-shifted in our earlier study, are now confirmed using another instrument: this time the 6.5m Clay telescope equipped with the MIKE spectrograph. The high signal-to-noise ratio (over 600) of our spectra allowed us to reveal even small small scale {\bf displacements} of positions (both: blue and red-shifts) of diffuse bands along the considered lines of sight. In some cases the magnitude of deviation exceeds 10 km\,s$^{-1}$. Also, we prove that profiles of many diffuse bands in spectra of HD34078 suffer significant broadening. The origin of the observed phenomena is discussed.