Volume 369, Number 3, April III 2001
|Page(s)||812 - 825|
|Section||Cosmology (including clusters of galaxies)|
|Published online||15 April 2001|
Deep VLT search for globular clusters in NGC 5128: Color-magnitude diagrams and globular cluster luminosity function*
European Southern Observatory, Karl-Schwarzschild-Strasse 2, 85748 Garching, Germany
2 Department of Astronomy, P. Universidad Católica, Casilla 306, Santiago 22, Chile
Corresponding author: M. Rejkuba, email@example.com
Accepted: 31 January 2001
At the distance of NGC 5128 ( Mpc) it is possible to resolve globular clusters with high resolution imaging from the ground, thus allowing the globular cluster candidate selection primarily through their morphological properties. I report the discovery of 71 globular clusters in NGC 5128 on VLT UT1+FORS1 images, including the faintest members () known to date in this galaxy as well as in 5 previously-known clusters. U- and V-band photometry has been measured for all the candidates and the luminosity function, spanning and , constructed. These are the deepest globular cluster luminosity functions in an elliptical galaxy determined so far. The Kolmogorov-Smirnov statistics show that the difference between the globular cluster luminosity functions of NGC 5128 and the MW is not larger than the difference between the ones of M 31 and the MW. The ()0 color histogram shows a bimodal distribution. For 23 globular clusters I obtained K-band images with SOFI at the NTT in La Silla. Their positions in the () vs. () color-color diagram indicate that they are indeed old globular clusters. Assuming that the globular clusters in NGC 5128 span a similar age range as the ones in the Milky Way and adopting a linear fit between the metallicity and ()0 color, the metal-rich clusters peak at dex and the metal-poor ones peak at dex.
Key words: galaxies: star clusters / galaxies: formation / galaxies: individual: NGC 5128
© ESO, 2001
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.