Dehydrogenation of polycyclic aromatic hydrocarbons in the diffuse interstellar medium

Content Provider	Semantic Scholar
Author	Foing, My Ha Vuong Bernard H.
Copyright Year	2000
Abstract	We present a model for the hydrogenation states of Polycyclic Aromatic Hydrocarbons (PAHs) in the diffuse interstellar medium. First, we study the abundance of hydrogenation and charge states of PAHs due to photo-ionization, photo-dissociation in the interstellar UV field, electron recombination and chemical reactions between PAH cations and H or H_2. For PAH cations, we find that the dehydrogenation effects are dominant. The hydrogenation state of PAHs depends strongly on the H density, the size of the molecule and UV field. In diffuse clouds with low H density and normal UV radiation, PAHs containing less than 40 C are completely or strongly dehydrogenated whereas at high H density, they are normally hydrogenated. The partially dehydrogenated species dominate in intermediate density clouds. PAHs above 40 C are quite stable and are fully hydrogenated, which would favor their spectroscopic search in near IR surveys of Diffuse Interstellar Bands (DIBs).
File Format	PDF HTM / HTML
Alternate Webpage(s)	https://arxiv.org/pdf/astro-ph/0010385v1.pdf
Alternate Webpage(s)	http://aa.springer.de/papers/0363001/23000l5.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article