摘要:We have used new wide-field imaging with the Magellan IMACS camera to search for globular cluster (GC) candidates around NGC 5128, the nearest giant E galaxy. The imaging data are in the B and R broadband filters and cover a 1.55 deg2 field centered on the galaxy, corresponding to an area about 90 × 90 kpc2 at the distance of NGC 5128. All the fields were taken under exceptionally high-quality seeing conditions (FWHM = 04-05 in R). Using this material we are able, for the first time in the literature, to construct a homogeneous list of GC candidates covering a wide span of the NGC 5128 halo and unusually free of field contaminants (foreground stars and faint background galaxies). Selecting the measured objects by color, magnitude, ellipticity, and profile size gives us a final catalog of 833 new high-quality GC candidates brighter than R = 21 (0.8 mag fainter than the standard GC luminosity function turnover point). The measured positions have better than 02 precision in both coordinates. This list can be used as the basis for spectroscopic follow-up, leading to a more comprehensive kinematic and dynamic study of the halo.
关键词:galaxies: elliptical and lenticular; cD;galaxies: individual (NGC 5128);galaxies: star clusters: general;globular clusters: general Online-only material: color figures; machine-readable and VO table