We have observed the hyperfine spectrum of <sup>130</sup>Te<sub>2</sub> that coincides with the visible emissions of an Ar<sup>+</sup> laser by using Doppler-free polarization spectroscopy. The vacuum wavelengths of the 16 transitions observed have been measured by a high-precision wavemeter with an uncertainty ranging from 6 parts in 10<sup>9</sup> in the best case to 1.4 parts in 10<sup>8</sup> in the worst case. These measurements provide a set of precise molecular references to frequency locking of visible lines of Ar<sup>+</sup> lasers used in high-precision laser spectrometers.
© 1997 Optical Society of America
P. Cancio and D. Bermejo, "Absolute wavelengths in 130Te2: new reference lines for laser spectroscopy coinciding with emissions of the Ar+ laser," J. Opt. Soc. Am. B 14, 1305-1311 (1997)