title: Communication: Saturated CO2 absorption near 1.6 μm for kilohertz-accuracy transition frequencies.
abstract: Doppler-free saturated-absorption Lamb dips were measured on weak rovibrational lines of (12)C(16)O2 between 6189 and 6215 cm(-1) at sub-Pa pressures using optical feedback frequency stabilized cavity ring-down spectroscopy. By referencing the laser source to an optical frequency comb, transition frequencies for ten lines of the 30013←00001 band P-branch and two lines of the 31113←01101 hot band R-branch were determined with an accuracy of a few parts in 10(11). Involving rotational quantum numbers up to 42, the data were used for improving the upper level spectroscopic constants. These results provide a highly accurate reference frequency grid over the spectral interval from 1599 to 1616 nm.
authors.affiliation: Univ. Grenoble Alpes, LIPhy, F-38000 Grenoble, France.
authors.forename: Johannes
authors.initials: J
authors.lastname: Burkart
authors.affiliation: Physics Department of Politecnico di Milano and IFN-CNR, Piazza Leonardo da Vinci 32, 20133 Milano, Italy.
authors.forename: Tommaso
authors.initials: T
authors.lastname: Sala
authors.affiliation: Univ. Grenoble Alpes, LIPhy, F-38000 Grenoble, France.
authors.forename: Daniele
authors.initials: D
authors.lastname: Romanini
authors.affiliation: Physics Department of Politecnico di Milano and IFN-CNR, Piazza Leonardo da Vinci 32, 20133 Milano, Italy.
authors.forename: Marco
authors.initials: M
authors.lastname: Marangoni
authors.affiliation: Univ. Grenoble Alpes, LIPhy, F-38000 Grenoble, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Campargue
authors.affiliation: Univ. Grenoble Alpes, LIPhy, F-38000 Grenoble, France.
authors.forename: Samir
authors.initials: S
authors.lastname: Kassi