On the Formation of Giant Elliptical Galaxies and Globular Clusters

Abstract

I review the current status of understanding when, how long, and how giant elliptical galaxies formed, focusing on the globular clusters. Several observational evidences show that massive elliptical galaxies formed at $z>2$ ($>10$ Gyr ago). Giant elliptical galaxies show mostly a bimodal color distribution of globular clusters, indicating a factor of $\approx 20$ metallicity difference between the two peaks. The red globular clusters (RGCs) are closely related with the stellar halo in color and spatial distribution, while the blue globular clusters (BGCs) are not. The ratio of the number of the RGCs and that of the BGCs varies depending on galaxies. It is concluded that the BGCs might have formed 12--13 Gyr ago, while the RGCs and giant elliptical galaxies might have formed similarly 10-11 Gyr ago. It remains now to explain the existence of a gap between the RGC formation epoch and the BGC formation epoch, and the rapid metallicity increase during the gap ($\Delta t\approx 2$ Gyr). If hierarchical merging can form a significant number of giant elliptical galaxies $>10$ Gyr ago, several observational constraints from stars and globular clusters in elliptical galaxies can be explained.

The proceedings of 28 pages, 14 figures (11 ps, 3 jpg), proceedings of APCTP 2nd Korean Astrophysics Workshop on "Formation and Interaction of Galaxies" (H.M.Lee & D. Ryu eds), to appear in the Journal of Korean Astronomical Society

References in corpus (34)

• Cosmological Results from High-z Supernovae
• Stellar population models of Lick indices with variable element abundance ratios
• A median redshift of 2.4 for galaxies bright at submillimetre wavelengths
• Formation of globular clusters in hierarchical cosmology
• Star Formation from Galaxies to Globules
• Measuring Distances and Probing the Unresolved Stellar Populations of Galaxies Using Infrared Surface Brightness Fluctuations
• GCD+: A New Chemodynamical Approach to Modeling SNe and Chemical Enrichment
• Early-type galaxies in the SDSS. IV. Colors and chemical evolution
• The Globular Cluster System of NGC 1399. I. A Wide-field Photometric Study
• Dynamics of the Globular Cluster System Associated with M49 (NGC4472): Cluster Orbital Properties and the Distribution of Dark Matter
• The Importance of Dry and Mixed Mergers for Early-Type Galaxy Formation
• Extragalactic Globular Clusters in the Near-Infrared II. The Globular Clusters Systems of NGC 3115 and NGC 4365
• Galaxy formation using halo merger histories taken from N-body simulations
• Simulations of Galaxy Formation in a Lambda CDM Universe III: The Dissipative Formation of an Elliptical Galaxy
• The K20 survey. IV. The redshift distribution of Ks<20 galaxies: a test of galaxy formation models
• The Ages and Abundances of a Sample of Globular Clusters in M49 (NGC 4472)
• A Young Blue Tidal Stream in NGC 5128
• What determines galactic evolution?
• Evidence for An Intermediate-Age, Metal-rich Population of Globular Clusters in NGC 4365
• The Relative Ages of the Globular Cluster Subpopulations in M87
• The impact of alpha/Fe enhanced stellar evolutionary tracks on the ages of elliptical galaxies
• Massive Ellipticals at High Redshift: NICMOS Imaging of Z~1 Radio Galaxies
• Extragalactic Globular Clusters in the Near Infrared I: A comparison between M87 and NGC 4478
• A Point Source Excess in Abell 1185: Intergalactic Globular Clusters?
• The quasar epoch and the stellar ages of early-type galaxies
• Simultaneous Modelling of the Stellar Halo and Globular Cluster System of NGC 5128
• Keck Spectroscopy of Globular Clusters in the Elliptical Galaxy NGC 3610
• Origin of the metallicity distribution of the NGC 5128 stellar halo
• Early Preheating and Galaxy Formation
• Globular Clusters in nearby Galaxy Cluster
• The formation and evolution of field massive galaxies
• Formation of Globular Clusters: In and Out of Dwarf Galaxies
• The Formation of Spheroidal Stellar Systems
• Observing Massive Galaxy Formation

Cited by in corpus (12)

• Detection of a Large Scale Structure of Intracluster Globular Clusters in the Virgo Cluster
• The Globular Cluster System of M60 (NGC 4649). II. Kinematics of the Globular Cluster System
• Washington CCD Photometry of the Globular Cluster System of the Giant Elliptical Galaxy M60 in Virgo
• The Globular Cluster System of the Virgo Giant Elliptical Galaxy NGC 4636: II. Kinematics of the Globular Cluster System
• A Catalog of Bright Star Clusters in the Interacting Galaxy M51
• The Globular Cluster System of M60 (NGC 4649). I. CFHT MOS Spectroscopy and Database
• The Nature of Blue Early-Type Galaxies in the Goods Fields
• The Star Cluster System in the Local Group Starburst Galaxy IC 10
• The Globular Cluster System of NGC 4636 and Formation of Globular Clusters in Giant Elliptical Galaxies
• SUBARU Spectroscopy of the Globular Clusters in the Virgo Giant Elliptical Galaxy M86
• The Globular Cluster System of the Virgo Giant Elliptical Galaxy NGC 4636: I. Subaru/FOCAS Spectroscopy and Database
• Wandering globular clusters: the first dwarf galaxies in the universe?