Astrochimistry – Spring 2013 Interstellar PAHs

I. From Unidentified to Aromatic Infrared Bands
I.1 Historical background
Gillett et al. (1967): IR excess in the ?? range compared to free-free radio continuum
extrapolation
Russell et al. (1977): unidentified IR bands at 3.3, 3.4, 6.2, 7.7, 8.6 & 11.3 µm from reflection
nebulea
Duley & Williams (1981): notice the match between some PAH spectral features and UIBs
Sellgren et al. (1983): near IR emission from reflection nebulae inconsistant
with UV-photons thermally excited dust grains => transient heating of small particles ?
Léger & Puget (1984): the “first first” attribution of UIBs to PAHs
(transient heating excitation model)
Allamandola, Tielens & Barker (1985): the “second first” attribution of UIBs to PAHs
(non thermal excitation model)
Désert et al. (1990): global model of dust grains including PAHs
1990': first big experiments and detailed theoretical models + Infrared Space Observatory era
2000': multiplication of experiments and detailed models + Spitzer Space Telescope era
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