  Deneb is often considered the prototypical A-type supergiant, and is one of
the visually most luminous stars in the Galaxy. A-type supergiants are
potential extragalactic distance indicators, but the variability of these stars
needs to be better characterized before this technique can be considered
reliable. We analyzed 339 high resolution echelle spectra of Deneb obtained
over the five-year span of 1997 through 2001 as well as 370 Stromgren
photometric measurements obtained during the same time frame. Our spectroscopic
analysis included dynamical spectra of the H-alpha profile, H-alpha equivalent
widths, and radial velocities measured from Si II 6347, 6371. Time-series
analysis reveals no obvious cyclic behavior that proceeds through multiple
observing seasons, although we found a suspected 40 day period in two,
non-consecutive observing seasons. Some correlations are found between
photometric and radial velocity data sets, and suggest radial pulsations at two
epochs. No correlation is found between the variability of the H-alpha profiles
and that of the radial velocities or the photometry. Lucy (1976) found evidence
that Deneb was a long period single-lined spectroscopic binary star, but our
data set shows no evidence for radial velocity variations caused by a binary
companion.
