Wide-field Washington photometry of the NGC 5128 globular cluster system. I. The database

To investigate the global properties of the globular cluster system (GCS) around NGC 5128, the central giant elliptical galaxy in the nearby Centaurus group, we have obtained deep CCD imaging for an area of almost 2 deg ² centered on the galaxy. Our data, in the CMT ¹ Washington photometric system, reach an approximate limiting magnitude of T ₁ ≃ R ≃ 22 and contain magnitudes, colors, and coordinates for more than 100,000 objects. Of these, the vast majority (about 99%) are either foreground stars or faint background galaxies; the old-halo globular clusters make up the remaining tiny fraction of the sample. Our database, however, provides the material for understanding the large-scale features of the GCS, including its metallicity distribution (MDF), luminosity distribution, and spatial structure.