We present the galaxy luminosity function (LF) of the Abell 119 cluster down to Mr ∼ -14 mag based on deep images in the u, g, and r bands taken by using MOSAIC II CCD mounted on the Blanco 4 m telescope at the CTIO. The cluster membership was accurately determined based on the radial velocity information and on the Color-magnitude relation for bright galaxies and the scaling relation for faint galaxies. The overall LF exhibits a bimodal behavior with a distinct dip at r ∼ 18.5 mag (Mr ∼ -17.8 mag), which is more appropriately described by a two-component function. The shape of the LF strongly depends on the clustercentric distance and on the local galaxy density. The LF of galaxies in the outer, low-density region exhibits a steeper slope and more prominent dip compared with that of counterparts in the inner, high-density region. We found evidence for a substructure in the projected galaxy distribution in which several overdense regions in the Abell 119 cluster appear to be closely associated with the surrounding, possible filamentary structure. The combined LF of the overdense regions exhibits a two-component function with a distinct dip, while the LF of the central region is well described by a single Schechter function. We suggest that, in the context of the hierarchical cluster formation scenario, the observed overdense regions are the relics of galaxy groups, retaining their two-component LFs with a dip, which acquired their shapes through a galaxy merging process in group environments, before they fall into a cluster.
Bibliographical noteFunding Information:
This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science, and Technology (2015R1A2A2A01006828). Support for this work was also provided by the NRF of Korea to the Center for Galaxy Evolution Research (No. 2010-0027910). This study was also financially supported by the research fund of Chungnam National University in 2014. Y.L. was supported by the Korea Astronomy and Space Science Institute under the R&D program supervised by the Ministry of Science, ICT, and Future Planning. S.K.Y. acknowledges support from the Korean National Research Foundation (NRF-2014R1A2A1A01003730). Y.-K.S. acknowledges support by FONDECYT Postdoctoral Fellowship (No. 3130470).
© 2016. The American Astronomical Society. All rights reserved.
All Science Journal Classification (ASJC) codes
- Astronomy and Astrophysics
- Space and Planetary Science