PRECISE WAVELENGTH MEASUREMENT OF SOME $Na_{2}$ AND $Li_{2}$ B-X TRANSITIONS VIA LASER ACTION IN THE DIMERS

$^{1}$ J. L. Hall and S. A. Lee, Appl. Phys. Lett. 29, 367 (1976) Alain Brillet has been on leave from Laboratoire de l'Horloge Atomique, CNRS V, Orsay, France.""Author Institution: Time and Frequency Division, National Bureau of Standards; Joint Institute for Laboratory Astrophysics, National Bureau of Standards and University of ColoradoWe have been able to measure some transitions in the $Na_{2}$ and $Li_{2}$ B-X system to an absolute accuracy of a few parts in $10^{7}$. A single frequency $Ar^{+}$ laser is used to excite the known coincidences and the resulting fluorescence progression is made to lase on a few of its stronger red members. The laser gain exhibits an A.C. stark-induced feature which allows precise location, of the line center. At this point the laser (transition) wavelength is measured using a ``Lambda Meter”.$^{1}