The hyperfine structure (hfs) of the <i>A</i><sup>2</sup>Π excited state of Ca<sup>35</sup>Cl has been investigated by using the new rf-pumped, laser-rf double-resonance technique. The optically unresolved hfs components of the <i>R</i><sub>2</sub> (<i>N</i>″ = 101), <i>A</i> ↔ <i>X</i> (0, 0) line were resolved by double resonance, and the measured splittings, when combined with the known <i>X</i><sup>2</sup>Σ<sup>+</sup>- state hfs spacings, show that the <i>A</i><sup>2</sup>Π -state hfs splittings are not more than 1 MHz.
© 1982 Optical Society of America
W. J. Childs, David R. Cok, and L. S. Goodman, "Hyperfine structure of the A 2Π state of Ca35Cl," J. Opt. Soc. Am. 72, 717-719 (1982)