Absolute Frequency Atlas of Molecular Lines at 532 nm

Abstract—With the aid of two iodine spectrometers, we report for the first time the measurement of the hyperfine splittings of the P(54) 32-0 and R(57) 32-0 transitions near 532 nm. Within the tuning range of the frequency-doubled Nd:YAG laser, modulation transfer spectroscopy recovers nine relatively strong ro-vibrational transitions of 127I 2 molecules with excellent SNR. These transitions are now linked together with their abso-lute frequencies determined by measuring directly the frequency gaps between each line and the R(56) 32-0:a 10 component. This provides an attractive frequency reference network in this wavelength region. Index Terms—Frequency control, frequency measurement, fre-quency modulation, laser spectroscopy, laser stability, measure-ment standards, YAG lasers. I