Document Type

Article

Publication Date

1-1-2013

Publication Title

Monthly Notices of the Royal Astronomical Society

Volume

436

First Page

1172

Last Page

1190

DOI

10.1093/mnras/stt1637

Disciplines

Astrophysics and Astronomy

Abstract

We use multipointing Hubble Space Telescope Advanced Camera for Surveys and wide field Subaru Suprime-Cam imaging to study the globular cluster system of the L* elliptical galaxy NGC 4278. We have also obtained a handful of new globular cluster spectra with the Keck Deep Imaging Multi-Object Spectrograph. We determine the globular cluster surface density profile and use it to calculate the total number of globular clusters, finding the system to be slightly more populous than average for galaxies of its luminosity. We find clear evidence for bimodality in the globular cluster colour distribution and for a colour–magnitude relation in the blue subpopulation (a ‘blue tilt’). We also find negative radial colour gradients in both colour subpopulations of equal strength which are similar in strength to those reported in other galaxies. The sizes of NGC 4278's globular clusters decrease with redder colours and increase with galactocentric radius. The ratio of the sizes of blue to red globular clusters is independent of galactocentric radius demonstrating that internal effects are responsible for the size difference with colour.

Comments

Copyright © 2013 Oxford University Press. The published article may be found at :http://dx.doi.org/10.1093/mnras/stt1637.

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