| Title | Polycyclic aromatic hydrocarbons and the diffuse interstellar bands: a survey. | | Author(s) | Salama F, Galazutdinov GA, Krelowski J, Allamandola LJ, Musaev FA | | Institution | NASA-Ames Research Center, Space Science Division, Moffett Field, CA 94035-1000, USA. fsalama@mail.arc.nasa.gov | | Source | Astrophys J 1999 Nov 20.:265-73. | | MeSH | Astronomy
Comparative Study
Cosmic Dust
Extraterrestrial Environment
Gases
Ions
Naphthalenes
Perylene
Polycyclic Hydrocarbons, Aromatic
Pyrenes
Research Support, Non-U.S. Gov't
Research Support, U.S. Gov't, Non-P.H.S.
Spectrum Analysis
| | Abstract | We discuss the proposal relating the origin of some of the diffuse interstellar bands (DIBs) to neutral and ionized polycyclic aromatic hydrocarbons (PAHs) present in interstellar clouds. Laboratory spectra of several PAHs, isolated at low temperature in inert gas matrices, are compared with the spectra of five reddened early-type stars selected from an extensive set of astronomical spectra. From this comparison, it is concluded that PAH ions are good candidates to explain some of the DIBS. Unambiguous assignments are difficult, however, because of the shift in wavelengths and the band broadening induced in the laboratory spectra by the solid matrix. This situation is illustrated by a comparison with the gas-phase spectra made available recently for two PAH ions. Definitive band assignments and, ultimately, the test of the proposal that PAH ions carry some of the DIBs must await the availability of a larger set of gas-phase measurements in the laboratory. The present assessment offers a guideline for future laboratory experiments by allowing the preselection of promising PAH molecules to be studied in jet expansions. | | Language | eng | | Pub Type(s) | Journal Article
| | PubMed ID | 11543306 |
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