  As part of a concentrated effort to understand and exploit better the seismic
properties of Feige 48, we reestimated its atmospheric parameters using, for
the first time, a self-consistent approach based on the detailed metal
abundances that have been determined in previous studies of both its UV and
optical spectrum. We computed a small 3D grid of 150 fully line-blanketed, NLTE
model atmospheres incorporating the 8 most abundant metals found in the
atmosphere of that star. We next compared quantitatively the synthetic spectra
that we calculated from these models with three observed spectra having
different resolutions (1 A, 6 A, and 8.7 A) and wavelength ranges. Our findings
are Teff = 29,890 K, log g = 5.46, and log N(He)/N(H) = -2.88, with very small
formal fitting errors. These estimates are in good agreement with those of
previous studies, thus showing that the presence of metals do not affect
significantly the bulk atmospheric properties of Feige 48. We also modeled the
He II line at 1640 A from the STIS spectrum of the star and we found with this
line an effective temperature and a surface gravity that match well the values
obtained with the optical data. We also present a radial velocity curve based
on several years of observing Feige 48 at the MMT. This curve indicates a
precise orbital period of 8.25 h. Coupled to our discovery of a weak but very
real periodicity of 8.25 h in the light curve of Feige 48, that was gathered
during a recent extensive photometric campaign at the Mount Bigelow 1.55 m
Kuiper Telescope, we conclude that there is a reflection effect in the system,
and that the unseen companion is a low mass MS star and not a white dwarf as
has been previously suggested.
