Cross sections for the ionization continuum of H2 in the 15.3-17.2 eV energy range

The absolute values for the cross sections of the ionization continuum of H2 had been measured at low energy (15.3-17.2 eV) Both absorption and ionization spectra were simultaneously recorded with linear response and absolute values, using a 10 m normal incidence monochromator installed on a synchrotron undulator beamline. The vibrational thresholds can be clearly seen as steps in the experimental data. The agreement between experimental values and theoretical ones is very good except around the first and second vibrational thresholds where the experimental data exceed the theoretical ones.