Selective excitation of the npsigma Sigma_u^+ and nppi Pi_u to E,F 1Sigma_g^+ emission systems in molecular hydrogen using synchrotron radiation

The states in H2 have been selectively excited using monoenergetic synchrotron light in the range 14.4-15.5 eV and the subsequent emission was observed using a grating spectrometer. In total 22 well separated bands to E,F systems (n=3-7) were observed and rotationally analysed. The intensities of the P and R branches relative to the Q branch vary strongly in the np? to EF bands confirming the existence of predissociations of a large number of View the MathML source levels. Energy levels of the E,F Sigma_g state (vE,F=0, 1, 3, 6-10) are obtained which confirm earlier determinations from other H2 experiments.