M.L. Niu, A.N. Heays, S. Jones, E.J. Salumbides, E.F. Van Dishoeck, N. De Oliveira, L. Nahon, W. Ubachs
Abstract Photoabsorption spectra of N2 and CO were recorded at 900 K, using the vacuum-ultraviolet Fourier-transform spectrometer at the DESIRS beamline of synchrotron SOLEIL. These high-temperature and high-resolution measurements allow for precise determination of line wavelengths, oscillator strengths, and predissociative line broadening of highly-excited rotational states with J up to about 50, and also vibrational hot bands. In CO, the perturbations of the A1Π-X1Σ+ vibrational bands (0,0) and (1,0) were studied, as well as the transitions to perturbing optically-forbidden states e3Σ-,d3Δ,D1Δ and a′3Σ+. In N2, we observed line shifts and broadening in several b1Πu-X1Σg+ bands due to unobserved forbidden states of 3Πu symmetry. The observed state interactions are deperturbed and, for N2, used to validate a coupled-channels model of the interacting electronic states. These data are appropriate for use in astrophysical or (exo-)planetary atmospheric applications where high temperatures are important and in future spectroscopic models of these molecules. © 2015 Elsevier Inc.
Department of Physics and Astronomy, LaserLaB, VU University, De Boelelaan 1081, Amsterdam, 1081, HV, Netherlands; Leiden Observatory, Leiden University, PO Box 9513, Leiden, 2300, RA, Netherlands; School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, United Kingdom; Department of Physics, University of San Carlos, Cebu City, 6000, Philippines; Synchrotron Soleil, Orme des Merisiers, St. Aubin BP 48, Gif sur Yvette cedex, 91192, France
