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.

14 pages, 18 figures, accepted for publication in MNRAS

References in corpus (5)

• The Formation and Evolution of Young Globular Clusters in NGC 3256
• Cold gas and star formation in a merging galaxy sequence
• Imaging of the protoelliptical NGC 1700 and its globular cluster system
• The Specific Frequency of Globular Clusters in Galaxies
• Imaging of the Merging Galaxy NGC 3597 and its Population of Proto--Globular Clusters

Cited by in corpus (5)

• Hubble Space Telescope observations of globular cluster systems along the Hubble sequence of spiral galaxies
• The Luminosity Functions of Old and Intermediate-Age Globular Clusters in NGC 3610
• Keck Imaging of the Globular Cluster Systems in the Early--type Galaxies NGC 1052 and NGC 7332
• Damp Mergers: Recent Gaseous Mergers without Significant Globular Cluster Formation?
• Formation Scenarios for Globular Clusters and Their Host Galaxies