Knowledge Bank

Heterodyne difference frequency measurements between a $\mathrm{<mrow\; data-mjx-texclass="ORD">13</mrow>}CO2$ laser and a diode laser tuned (and in most cases locked) to the peaks of OCS absorption lines have been used to improve frequency calibration tables in the $860cm-1$ region by factor of 20 to 50. Measurements have been made on the vibrational transitions $10\circ 0-00\circ 0,111e0-o11e0,111f0-011f0$, and $20^{\circ}0-10^{\circ}$0 for $\mathrm{<mrow\; data-mjx-texclass="ORD">16</mrow>}012C32S$ and on the $10\circ 0-00\circ 0$ and $\mathrm{<mrow\; data-mjx-texclass="ORD">11</mrow>}10-0110$ transitions for $\mathrm{<mrow\; data-mjx-texclass="ORD">16</mrow>}O13C32S$. The measurements on the $10\circ 0-00\circ 0$ and $20\circ 0-10\circ 0$ transitions can also be used to provide frequency calibration tables for the $20\circ 0-00\circ 0$ band of OCS near $1700cm-1$.