title: High-resolution 2 + 1 REMPI study of the a''1Sigma(g)+ state in N2.
abstract: We reinvestigated the 2 + 1 REMPI Q-branch spectrum of the a''1Sigma(g)+-X1Sigma(g)+ system of N2 at around 202 nm in a Doppler-free configuration with counterpropagating laser beams. Highly accurate absolute calibrations were performed using either an I2 reference standard or a frequency comb reference laser. The observed rotational series shows a clear effect of a perturbation in terms of an anticrossing located at J = 26. In addition to the improved set of molecular constants for the a''1Sigma(g)+ state, we tentatively assign the perturber state to be the 1Sigma(g)+(II) state of N2.
authors.affiliation: Laser Centre, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands.
authors.forename: E J
authors.initials: EJ
authors.lastname: Salumbides
authors.forename: A
authors.initials: A
authors.lastname: Khramov
authors.forename: W
authors.initials: W
authors.lastname: Ubachs