Structural Parameters for Globular Clusters in NGC 5128. II: HST/ACS Imaging and New Clusters

Abstract

We report the first results from an imaging program with the ACS camera on HST designed to measure the structural characteristics of a wide range of globular clusters in NGC 5128, the nearest giant elliptical galaxy. From 12 ACS/WFC fields, we have measured a total of 62 previously known globular clusters and have discovered 69 new high-probability cluster candidates not found in any previous work. We present magnitudes and color indices for all of these, along with rough measurements of their effective diameters and ellipticities. The luminosity distribution of this nearly-uncontaminated sample of clusters matches well with the normal GCLF for giant elliptical galaxies, and the cluster scale size and ellipticity distributions are similar to those in the Milky Way system. The indication from this survey is that many hundreds of individual clusters remain to be found with carefully designed search techniques in the future. A very rough estimate of the total cluster population from our data suggests N_GC = 1500 in NGC 5128, over all magnitudes and within a projected radius R = 25' from the galaxy center.

AASTex, 33 preprint pages including 9 Figures. Accepted for publication in Astronomical Journal, volume 132 (2006)

References in corpus (18)

• Resolved Massive Star Clusters in the Milky Way and its Satellites: Brightness Profiles and a Catalogue of Fundamental Parameters
• Properties of Globular Cluster Systems in Nearby Early-type Galaxies
• The ACS Virgo Cluster Survey. VII. Resolving the Connection Between Globular Clusters and Ultra-Compact Dwarf Galaxies
• A class of compact dwarf galaxies from disruptive processes in galaxy clusters
• The ACS Virgo Cluster Survey X. Half-light Radii of Globular Clusters in Early-Type Galaxies: Environmental Dependencies and a Standard Ruler for Distance Estimation
• Ultra-Compact Dwarf Galaxies in the Fornax Cluster
• Binding Energy and the Fundamental Plane of Globular Clusters
• The Planetary Nebula System and Dynamics in the Outer Halo of NGC 5128
• A new population of extended, luminous star clusters in the halo of M31
• The Globular Cluster System of NGC 5128 II. Ages, Metallicities, Kinematics, and Formation
• Deep ACS Imaging of the Halo of NGC 5128: Reaching the Horizontal Branch
• Discovery of Ultra-Compact Dwarf Galaxies in the Virgo Cluster
• A Population of Massive Globular Clusters in NGC 5128
• Structural Parameters for Globular Clusters in NGC 5128
• Deep VLT search for globular clusters in NGC 5128: color-magnitude diagrams and globular cluster luminosity function
• Radial Velocities of Newly Discovered Globular Clusters in NGC 5128
• Structural Parameters from Ground-based Observations of Newly Discovered Globular Clusters in NGC 5128
• A Color-Magnitude Diagram for a Globular Cluster In the Giant Elliptical Galaxy NGC 5128

Cited by in corpus (33)

• The Observed properties of Dark Matter on small spatial scales
• Structural parameters for globular clusters in M31 and generalizations for the fundamental plane
• Globular Cluster Systems in Nearby Dwarf Galaxies: I. HST/ACS Observations and Dynamical Properties of Globular Clusters at Low Environmental Density
• A 2dF spectroscopic study of globular clusters in NGC 5128: Probing the formation history of the nearest giant Elliptical
• Globular clusters in the outer halo of M31: the survey
• The Kinematics of the Globular Cluster System of NGC 5128 with a New, Large Sample of Radial Velocity Measurements
• The connection between globular cluster systems and their host galaxy and environment: a case study of the isolated elliptical NGC 821
• The Kinematics and Dynamics of the Globular Clusters and the Planetary Nebulae of NGC 5128
• Structural parameters for globular clusters in NGC 5128. III. ACS surface-brightness profiles and model fits
• Wide-Field Hubble Space Telescope Observations of the Globular Cluster System in NGC1399
• Low-Mass X-ray Binaries and Globular Clusters in Centaurus A
• The Globular Cluster System of the Virgo Giant Elliptical Galaxy NGC 4636: II. Kinematics of the Globular Cluster System
• Extending the baseline: Spitzer Mid-Infrared Photometry of Globular Cluster Systems in the Centaurus A and Sombrero Galaxies
• The Survey of Centaurus A's Baryonic Structures (SCABS). II. The Extended Globular Cluster System of NGC5128 and its Nearby Environment
• New g'r'i'z' Photometry of the NGC 5128 Globular Cluster System
• A Gaia-based catalog of candidate stripped nuclei and luminous globular clusters in the halo of Centaurus A
• The Flattening of Globular Clusters
• Sizes of Confirmed Globular Clusters in NGC 5128: A Wide-Field High-Resolution Study
• NGC 5128 globular cluster candidates out to 150 kpc: a comprehensive catalog from Gaia and ground based data
• WFCAM Survey of M31 Globular Clusters: Low Mass X-ray Binaries
• A SLUGGS and Gemini/GMOS combined study of the elliptical galaxy M60: wide-field photometry and kinematics of the globular cluster system
• The Globular Cluster System of NGC 5128: Ages, Metallicities, Kinematics, and Structural Parameters
• Scaling relations for globular cluster systems in early-type galaxies
• Globular Cluster Systems of Spiral and S0 Galaxies: Results from WIYN Imaging of NGC1023, NGC1055, NGC7332 and NGC7339
• Globular Clusters and Dwarf Spheroidal Galaxies
• Globular Clusters and X-ray Point Sources in Centaurus A (NGC 5128)
• A faint extended cluster in the outskirts of NGC 5128: evidence of a low mass accretion
• The Light Element Abundance Distribution in NGC 5128 from Planetary Nebulae
• New Velocity Measurements of NGC 5128 Globular Clusters out to 130 kpc: Outer Halo Kinematics, Substructure and Dynamics
• A Comparison Between the Globular Clusters in NGC 5128 and the Galaxy
• Shapes of dark matter haloes with discrete globular cluster dynamics: The example of NGC 5128 (Centaurus A)
• Probing cool giants in unresolved galaxies using fluctuation eigenspectra: a demonstration using high-resolution MUSE observations of NGC 5128
• Decomposing cool stellar populations with H-band spectral fluctuations: Long-period variable stars in NGC 5128 and carbon stars in NGC 5102