Observation of the y1Πg–c4′1Σ+u and k1Πg–c4′1Σ+u systems of N2

We observed the Λ-doublet of both parity components of the (1, 0) band of the y 1Πg–c4′ 1Σ+u and k 1Πg–c4′ 1Σ+u systems of molecular nitrogen in an extreme ultraviolet (XUV) + infrared (IR) double resonance experiment. The (e) components as well as the (f) components are observed up to J=21 in the case of the y state and up to J=17 in the case of the k state. Apart from mutual interaction between y 1Πg and k 1Πg, the (e) components undergo additional perturbations giving rise to predissociation.