title: Jet-discharge cavity ring-down spectroscopy of ionized polycyclic aromatic hydrocarbons: progress in testing the PAH hypothesis for the diffuse interstellar band problem.
abstract: Naphthalene cations (C10H+8) were produced in a slit jet coupled with an electronic discharge, and cavity ring down was used to obtain its absorption spectrum in the region 645-680 nm. Two of the strongest C10H+8 bands previously characterized by matrix isolation spectroscopy were found, both with a fractional blue shift of about 0.5%. This is the first gas-phase electronic absorption spectrum of an ionized polycyclic aromatic hydrocarbon (PAH). This work opens the way for a direct comparison of laboratory PAH spectra with the diffuse interstellar bands (DIB), the origin of which still constitutes an open problem in astrophysics.
authors.affiliation: Laboratoire de Spectrometrie Physique, Universite J. Fourier, Grenoble, France.
authors.forename: D
authors.initials: D
authors.lastname: Romanini
authors.forename: L
authors.initials: L
authors.lastname: Biennier
authors.forename: F
authors.initials: F
authors.lastname: Salama
authors.forename: A
authors.initials: A
authors.lastname: Kachanov
authors.forename: L J
authors.initials: LJ
authors.lastname: Allamandola
authors.forename: F
authors.initials: F
authors.lastname: Stoeckel
mesh_terms: D055580:Astronomical Phenomena; D001256:Astronomy; D005069:Evaluation Studies as Topic; D018559:Exobiology; D005118:Extraterrestrial Environment; D013058:Mass Spectrometry / Q000379:methods; D009281:Naphthalenes / Q000737:chemistry*; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D013696:Temperature
chemical_list: D009281:Naphthalenes; D011084:Polycyclic Aromatic Hydrocarbons; C031721:naphthalene