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Title: Polycyclic aromatic hydrocarbons and the unidentified infrared emission bands: Auto exhaust along the Milky Wayexclamation

Journal Article · · Astrophys. J., Lett. Ed.; (United States)
DOI:https://doi.org/10.1086/184435· OSTI ID:5773044

We have attributed the unidentified infrared emission feature (UIR bands) to a collection of partially hydrogenated, positively charged polycyclic aromatic hydrocarbons (PAHs). This assignment is based on a spectrocopic analysis of the UIR bands. Comparison of the observed interstellar 6.2 and 7.7 ..mu..m bands with the laboratory measured Raman spectrum of a collection of carbon-based particulates (auto exhaust) shows a very good agreement, supporting this idenfication. The infrared-emission is due to relaxation from highly vibrationally and electronically excited states. The infrared emission is due to relaxation from highly vibrationally excited states. The excitation is probably caused by UV photon absorption.

Research Organization:
Space Science Division, NASA/Ames Research Center
OSTI ID:
5773044
Journal Information:
Astrophys. J., Lett. Ed.; (United States), Vol. 290:1
Country of Publication:
United States
Language:
English