The globular cluster system of the young elliptical NGC 6702
Abstract
We study the globular cluster (GC) system of the dust-lane elliptical galaxy NGC 6702, using B, V and I-band photometric observations carried out at the Keck telescope. This galaxy has a spectroscopic age of ~2Gyrs suggesting recent star-formation. We find strong evidence for a bimodal GC colour distribution, with the blue peak having a colour similar to that of the Galactic halo GCs. Assuming that the blue GCs are indeed old and metal-poor, we estimate an age of 2-5Gyrs and supersolar metallicity for the red GC subpopulation. Despite the large uncertainties, this is in reasonable agreement with the spectroscopic galaxy age. Additionally, we estimate a specific frequency of S_{N}=2.3\pm1.1 for NGC 6702. We predict that passive evolution of NGC 6702 will further increase its specific frequency to S_{N}~2.7 within 10Gyrs, in closer agreement to that of typical present-day ellipticals. We also discuss evidence that the merger/accretion event that took place a few Gyrs ago involved a high gas fraction.
Keywords
Cite
@article{arxiv.astro-ph/0011275,
title = {The globular cluster system of the young elliptical NGC 6702},
author = {A. Georgakakis and D. A. Forbes and J. P. Brodie},
journal= {arXiv preprint arXiv:astro-ph/0011275},
year = {2009}
}
Comments
14 pages, 18 figures, accepted for publication in MNRAS