Abstract
ABSTRACT
Compact disc galaxies (CDGs) with high-surface brightness were identified in the Sloan Digital Sky Survey data. We determined the surface profiles of the CDGs and compared them to those of normal-sized disc galaxies (NDGs). The CDGs have higher central brightness and older stellar age than the NDGs. Furthermore, the brightness profiles of the CDGs fit a Sérsic model with n ≈ 2.11 and have a zero g′ − r′ colour gradient on average. By contrast, the NDGs fit an exponential profile and have a negative colour gradient on average. These results indicate that the structure and stellar population of the CDGs and NDGs differ. We suggest that the CDGs are ancient galaxies in the quenching phase following the initial central starburst.
Funder
Ministry of Science and Technology of Taiwan
Alfred P. Sloan Foundation
U.S. Department of Energy
Publisher
Oxford University Press (OUP)
Subject
Space and Planetary Science,Astronomy and Astrophysics