Knowledge Bank

Three bands of the $C-X2II$ system at $2063\backslash AA$, $2095\backslash AA$ and $2128\backslash AA$ and the $0-0,0-1,1-1$ and 1-2 bands of the $E-X2II$ system in the region $1800\backslash AA-1950\backslash AA$, belonging to the PO molecule, have been photographed at high resolution. A rotational analysis of these bands establishes the C and E states as $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Sigma$ and $\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}\Delta$ respectively. A perturbation in the E state is also observed. These results and the constants for the C and E states will be presented.