An autoionizing resonance in molecular N2 is excited by an ultrashort XUV
pulse and probed by a subsequent weak IR pulse, which ionizes the contributing
Rydberg states. Time- and angular-resolved photoelectron spectra recorded with
a velocity map imaging spectrometer reveal two electronic contributions with
different angular distributions. One of them has an exponential decay rate of
20 ± 5 fs, while the other one is shorter than 10 fs. This observation is
interpreted as a manifestation of interference stabilization involving the two
overlapping discrete Rydberg states. A formalism of interference stabilization
for molecular ionization is developed and applied to describe the autoionizing
resonance. The results of calculations suggest, that the effect of the
interference stabilization is facilitated by rotationally-induced couplings of
electronic states with different symmetry