Rotational relaxation measurements on OCS using a beam maser

Rotational relaxation cross sections are reported for J = 0, 1 and 2 rotational states of OCS using a variety of polar and non-polar scattering gases. Cross sections are reported for pure states, superposition states and total beam attenuation. Inelastic cross sections for symmetric top scattering molecules are much larger than corresponding cross sections for linear scattering molecules. Upper and lower states for both J = 0 → 1 and J = 1 → 2 transitions were selected using quadrupole or co-axial focusers. These preliminary results show differences in cross sections for different rotational states.