| Title | Globular cluster systems of early-type galaxies in low-density environments |
| Authors | Cho, J.; Sharples, R. M.; Blakeslee, J. P.; Zepf, S. E.; Kundu, A.; Kim, H. -S.; Yoon, S. -J. |
| Bibcode | 2012MNRAS.422.3591C Search ADS ↗ |
| Abstract | Deep images of 10 early-type galaxies in low-density environments have been obtained with the Advanced Camera for Surveys (ACS) aboard the Hubble Space Telescope. The global properties of the globular cluster (GC) systems of the galaxies have been derived in order to investigate the role of the environment in galaxy formation and evolution. Using the ACS Virgo Cluster Survey as a high-density counterpart, the similarities and differences between the GC properties in high- and low-density environments are presented. We find a strong correlation of the GC mean colours and the degree of colour bimodality with the host galaxy luminosity in low-density environments, in good agreement with high-density environments. In contrast, the GC mean colours at a given host luminosity are somewhat bluer [∆(g-z) ̃ 0.05] than those for cluster galaxies, indicating more metal poor (∆[Fe/H] ̃ 0.10 - 0.15) and/or younger (∆age > 2 Gyr) GC systems than those in dense environments. Furthermore, with decreasing host luminosity, the colour bimodality disappears faster, when compared to galaxies in cluster environments. Our results suggest that: (1) in both high- and low-density environments, the mass of the host galaxy has the dominant effect on GC system properties; (2) the local environment has only a secondary effect on the history of GC system formation; and (3) GC formation must be governed by common physical processes across a range of environments. Column (1): galaxy name; column (2): absolute B magnitude; column (3): RA; column (4): Dec.; column (5): morphological type; column (6): distance modulus; column (7): total apparent B magnitude; column (8): Galactic reddening; column (9): local density. Notes. The morphological type and apparent B magnitude are taken from NED. The distance moduli are SBF values from Tonry et al. (2001) except for IC 2035 where the distance modulus was estimated using the redshift from NED. The Galactic extinction is taken from Schlegel, Finkbeiner & Davis (1998) and the local density was obtained from Tully (1988). |
| Objects | 10 Objects Search NED ↙ |
