%0 Journal Article %1 GMS12b %A Glass-Maujean, M. %A Schmoranzer, H %A Haar, I %A Knie, A %A Reiss, P %A Ehresmann, A %D 2012 %J J. Chem. Phys. %K imported %P 1--10 %T The $J = 2$ ortho levels of the $v = 0$ to $6$ $np$ singlet Rydberg series of molecular hydrogen revisited %V 137 %X The energies and the widths of the J = 1 para levels of the v = 0 to 6 Rydberg np singlet series of molecular hydrogen with absolute intensities of the R(0) and P(2) absorption lines were measured by a high - resolution synchrotron radiation experiment and calculated through a full ab initio multichannel quantum defect theory approach. On the basis of the agreement between theory and experiment, 31 levels were either reassigned or assigned for the first time.