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We analyze three-band HST/ACS imaging data of the giant elliptical galaxyESO325-G004. This is the nearest known strongly lensing galaxy, and it residesin the center of the poor cluster Abell S0740 at redshift z=0.034. Based onmagnitude, color, and size selection criteria, we identify a sample of 15ultra-compact dwarf (UCD) galaxy candidates within the ACS field. This iscomparable to the numbers of UCDs found within similar regions in more nearbyclusters (Virgo, Fornax, Hydra). We estimate circular half-light radii R_e,cfrom 2-D Sersic and King model fits and apply an upper cutoff of 100pc for ourUCD selection. The selected galaxies have typical Sersic indices $n\approx1.5$,while larger sources with R_e,c > 100pc are more nearly exponential, perhapsindicating that the latter are dominated by background disk galaxies. Many ofthe UCD candidates are surrounded by a faint "fuzz" of halo light, which may bethe remnants of stripped material, and there is some evidence for intrinsicflattening of the UCDs themselves. An apparent separation in size between themost compact UCDs with R_e,c < 17pc and larger ones with R_e,c > 40pc may hintat different formation mechanisms. We do not find any M32 analogues in thisfield. The colors of the UCD candidates span the range from blue to redglobular clusters, although the brightest ones are predominantly red. The UCDcandidates follow the flattened, elliptical distribution of the globularclusters, which in turn follow the galaxy halo light, suggesting a commonevolution for these three components. Follow-up spectroscopy can determinewhich candidates are truly members of Abell S0740 and how similar they are indistribution to the globulars.

Ultra-Compact Dwarf Candidates Near the Lensing Galaxy in Abell S0740