title: Spectroscopic investigation of the A and 3 1Σ+ states of 39K85Rb.
abstract: By using a combination of molecular beam (MB) excitation spectra and two distinct ultracold molecule excitation spectra (UM+ and UM-), we have assigned high vibrational levels of the A and 3 (1)Σ(+) states from absorption spectra of the mutually strongly perturbed A (1)Σ(+) - 3 (1)Σ(+) - 1 (1)Π - 2 (3)Σ(+) - b (3)Π states of ultracold (39)K(85)Rb molecules in the energy region between 15,116 and 16,225 cm(-1) above the minimum of the ground X (1)Σ(+) state. The ultracold molecules (UM+ and UM-) are formed by radiative decay following photoassociation (PA) to a specific level of the 3(0(+)) state (UM+) or to a specific level of the 3(0(-)) state (UM-). We observe that the A and 3 (1)Σ(+) states are observable in the UM+ spectra, but absent from the UM- spectra. This is explained by considering Hund's case (c) selection rules and transition dipole moments between the upper excited A (1)Σ(+) (2(0(+))) state and the three Ω components (0(+), 0(-), and 1) at the ground-state dissociation limit. We propose further investigations of the extended potential wells of the A and 3 (1)Σ(+) states by combining short-range MB excitation spectra in a narrow Franck-Condon (FC) window near R(e) of the X (1)Σ(+) state, and long-range UM (and PA) excitation spectra, which have much larger FC windows.
authors.affiliation: Department of Photonic Engineering, Chosun University, Gwangju 501-759, Korea.
authors.forename: Jin-Tae
authors.initials: JT
authors.lastname: Kim
authors.forename: Yonghoon
authors.initials: Y
authors.lastname: Lee
authors.forename: Bongsoo
authors.initials: B
authors.lastname: Kim
authors.forename: Dajun
authors.initials: D
authors.lastname: Wang
authors.forename: Phillip L
authors.initials: PL
authors.lastname: Gould
authors.forename: Edward E
authors.initials: EE
authors.lastname: Eyler
authors.forename: William C
authors.initials: WC
authors.lastname: Stwalley