ON THE VIABILITY OF THE PAH MODEL AS AN EXPLANATION OF THE UNIDENTIFIED INFRARED EMISSION FEATURES

2014/10/24 by Yong Zhang, Sun Kwok · 38 citations
Physics and Astronomy · #Astro and Planetary Science #Astrochemistry #Astronomy and Astrophysical Research #Astrophysics and Star Formation Studies #Cosmic dust #Emission spectrum #Infrared #Infrared spectroscopy #Interstellar medium #Polycyclic aromatic hydrocarbon #Spectral line #astro-ph.SR

paper · pdf · doi:10.1088/0004-637x/798/1/37

published in The Astrophysical Journal 798(1), 37 (IOP Publishing) · 19 pages, 9 figures, accepted for publication in ApJ

arxiv created 2014/10/24 · openalex publication_date 2014/12/18 · arxiv updated 2015/06/23 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05

Abstract

Polycyclic aromatic hydrocarbon (PAH) molecules are widely considered the preferred candidate for the carrier of the unidentified infrared emission bands observed in the interstellar medium and circumstellar envelopes. In this paper, we report the results of fitting a variety of non-PAH spectra (silicates, hydrogenated amorphous carbon, coal, and even artificial spectra) using the theoretical infrared spectra of PAHs from the NASA Ames PAH IR Spectroscopic Database. We show that these non-PAH spectra can be well fitted by PAH mixtures. This suggests that a general match between astronomical spectra and those of PAH mixtures does not necessarily provide definitive support for the PAH hypothesis.

Citations

• The Role of Polycyclic Aromatic Hydrocarbons in Ultraviolet Extinction. I. Probing Small Molecular Polycyclic Aromatic Hydrocarbons
• UNIDENTIFIED INFRARED EMISSION BANDS: PAHs or MAONs?
• Abundances of PAHs in the ISM: confronting observations with experimental results
• Mixed aromatic–aliphatic organic nanoparticles as carriers of unidentified infrared emission features
• The Composition and Distribution of Dust along the Line of Sight toward the Galactic Center