Diffuse interstellar bands - an observational review (Review).
Abstract
This paper presents a review of observational data concerning the unidentified diffuse interstellar bands (DIBs). The history of the investigation of these fascinating spectral features is presented together with very recent results obtained with the aid of solid state detectors. The high signal-to-noise spectra allowed to divide diffuse bands into at least 3 families defined as sets of these features characterized by constant intensity ratios in every observed spectrum. 'Intrinsic' profiles of DIBs, i.e., profiles that originated in single interstellar clouds free of any Doppler splitting were derived from high resolution spectra. The same observations revealed convincingly the Doppler structures inside DIB profiles observed in distant objects. It is shown that DIBs may originate in clouds of very low opacity - their agent(s) being thus resistant against diffuse UV radiation. The agent(s) seems not to be the dust causing the visual extinction as the bands may be absent in some of reddened spectra. Relations between DIBs and other interstellar absorptions are also briefly reviewed.
- Publication:
-
Astronomische Nachrichten
- Pub Date:
- 1989
- DOI:
- 10.1002/asna.2113100403
- Bibcode:
- 1989AN....310..255K
- Keywords:
-
- Astronomical Spectroscopy;
- Diffuse Radiation;
- Interstellar Extinction;
- Interstellar Matter;
- Signal To Noise Ratios;
- Spectral Bands;
- Doppler Effect;
- Line Of Sight;
- Ultraviolet Radiation;
- Astrophysics