Early Results from the APO Diffuse Interstellar Band Survey
Abstract
The diffuse interstellar bands (DIBs) are absorption features observed in the visible spectra of nearly all red- dened stars, and were first observed in the early decades of the 20th century when many lines in astronomical spectra were unassigned. As laboratory spectroscopy progressed, most of the stronger lines were identified with atomic or diatomic species the DIBs are those lines (more numerous and generally broader) that remain unidentified.
Since the DIBs have remained unassigned for over 75 years despite extensive laboratory efforts, we are trying a new approach. Our goal is to obtain moderate resolution (λδλ ± 37,500), high signal-to-noise spectra of a large sample of reddened stars. We are using the ARCES echelle spectrograph at the Apache Point Observatory, which offers complete spectral coverage from 3700-1O,000Å. So far, we have taken data on 75 nights and have obtained S/N > 1000 on 63 stars, and S/N > 500 on 60 additional stars. Our hope is that this extensive DIB dataset, coupled with complementary measurements of known species at ultraviolet, visible, and infrared wavelengths, will yield new insights into the origin of the DIBs this paper presents some of onr early results.- Publication:
-
NASA Laboratory Astrophysics Workshop
- Pub Date:
- November 2002
- Bibcode:
- 2002nla..work..138M