  We measure the photoionization cross-section of vibrationally excited levels
in the S2 state of azulene by femtosecond pump-probe spectroscopy. At the
wavelengths studied (349-265 nm in the pump) the transient signals exhibit two
distinct and well-defined behaviours: (i) Short-term (on the order of a
picosecond) polarization dependent transients and (ii) longer (10 ps - 1 ns)
time-scale decays. This letter focuses on the short time transient. In contrast
to an earlier study by Diau et al.22 [J. Chem. Phys. 110 (1999) 9785.] we
unambiguously assign the fast initial decay signal to rotational dephasing of
the initial alignment created by the pump transition.
