title: Radiative cooling of C₇⁻.
abstract: The spontaneous and photo-induced neutralization of C₇⁻ produced in a laser ablation source was measured in an electrostatic storage ring. The measurements provide three independent determinations of the radiative cooling of the ions, based on the short time spontaneous decay and on the integrated amplitude and the shape of the photo-induced neutralization signal. The amplitude of the photo-induced signal was measured between 0.5 ms and 35 ms and found to depend on photon wavelength and ion storage time. All three signals can be reproduced with identical thermal IR radiative cooling rates with oscillator strengths equal to theoretical predictions. In addition, the measurements provide the excitation energy distribution.
authors.affiliation: Department of Physics, University of Gothenburg, 41296 Gothenburg, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Najafian
authors.affiliation: Department of Physics, University of Gothenburg, 41296 Gothenburg, Sweden.
authors.forename: M S
authors.initials: MS
authors.lastname: Pettersson
authors.affiliation: Applied Physics, Chalmers Technical University, Gothenburg, Sweden.
authors.forename: B
authors.initials: B
authors.lastname: Dynefors
authors.affiliation: Department of Chemistry, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachiouji-shi, Tokyo 192-0397, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Shiromaru
authors.affiliation: Department of Chemistry, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachiouji-shi, Tokyo 192-0397, Japan.
authors.forename: J
authors.initials: J
authors.lastname: Matsumoto
authors.affiliation: Department of Physics, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachiouji-shi, Tokyo 192-0397, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Tanuma
authors.affiliation: Department of Physics, Tokyo Metropolitan University, 1-1 Minamiosawa, Hachiouji-shi, Tokyo 192-0397, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Furukawa
authors.affiliation: Atomic, Molecular and Optical Physics Laboratory, RIKEN, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Azuma
authors.affiliation: Department of Physics, University of Gothenburg, 41296 Gothenburg, Sweden.
authors.forename: K
authors.initials: K
authors.lastname: Hansen