  High-dispersion spectra of 333 stars in the open cluster NGC 6819, obtained
using the HYDRA spectrograph on the WIYN 3.5m telescope, have been analyzed to
determine the abundances of iron and other metals from lines in the 400 A
region surrounding the Li 6708 A line. Our spectra, with signal-to-noise per
pixel (SNR) ranging from 60 to 300, span the luminosity range from the tip of
the red giant branch to a point two magnitudes below the top of the cluster
turnoff. We derive radial and rotational velocities for all stars, as well as
[Fe/H] based on 17 iron lines, [Ca/H], [Si/H], and [Ni/H] in the 247 most
probable, single members of the cluster. Input temperature estimates for model
atmosphere analysis are provided by (B-V) colors merged from several sources,
with individual reddening corrections applied to each star relative to a
cluster mean of E(B-V) = 0.16. Extensive use is made of ROBOSPECT, an automatic
equivalent width measurement program; its effectiveness on large spectroscopic
samples is discussed. From the sample of likely single members, [Fe/H] = -0.03
+/- 0.06, where the error describes the median absolute deviation about the
sample median value, leading to an internal precision for the cluster below
0.01 dex. The final uncertainty in the cluster abundance is therefore dominated
by external systematics due to the temperature scale, surface gravity, and
microturbulent velocity, leading to [Fe/H] = -0.02 +/- 0.02 for a sub-sample
restricted to main sequence and turnoff stars. This result is consistent with
our recent intermediate-band photometric determination of a slightly subsolar
abundance for this cluster. [Ca/Fe], [Si/Fe], and [Ni/Fe] are determined to be
solar within the uncertainties. NGC 6819 has an abundance distribution typical
of solar metallicity thin disk stars in the solar neighborhood.
