title: Ultraviolet spectroscopy of pyrene in a supersonic jet and in liquid helium droplets.
abstract: In a series of experiments devoted to the study of polycyclic aromatic hydrocarbons for astrophysical applications, the S(2)<--S(0) transition of jet-cooled pyrene (C(16)H(10)) at 321 nm has been studied by an absorption technique for the first time. The spectra observed by cavity ring-down spectroscopy closely resemble the excitation spectra obtained earlier by laser-induced fluorescence (LIF) and show the same band clusters arising from the vibronic interaction of S(2) with S(1). We have also investigated pyrene when it was incorporated into 380 mK cold helium droplets. These spectra which were recorded employing LIF and molecular beam depletion spectroscopy are broadened and redshifted by 0.94 nm but retain the essential features of the gas phase spectra.
authors.affiliation: Max-Planck-Institut fur Astronomie, Konigstuhl 17, D-69117 Heidelberg, Germany.
authors.forename: Gael
authors.initials: G
authors.lastname: Rouille
authors.forename: Serge
authors.initials: S
authors.lastname: Krasnokutski
authors.forename: Friedrich
authors.initials: F
authors.lastname: Huisken
authors.forename: Thomas
authors.initials: T
authors.lastname: Henning
authors.forename: Oleksandr
authors.initials: O
authors.lastname: Sukhorukov
authors.forename: Angela
authors.initials: A
authors.lastname: Staicu