천문학회보 (The Bulletin of The Korean Astronomical Society)
- 제40권2호
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- Pages.30.2-30.2
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- 2015
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- 1226-2692(pISSN)
Compact Stellar Systems and Dwarf Galaxies in the Pandora's Cluster Abell 2744
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Lee, Myung Gyoon
(Department of Physics and Astronomy, Seoul National University) ;
- Jang, In Sung (Department of Physics and Astronomy, Seoul National University)
- 발행 : 2015.10.15
초록
Abell 2744 is a giant merging cluster, called the Pandora's Cluster, at the redshift of z=0.308 (corresponding to a distance of 1270 Mpc). Taking the advantage of the deep high resolution images in the Hubble Frontier Field program, we study the properties of compact stellar systems including globular clusters and ultracompact dwarfs (UCDs) as well as dwarf galaxies in this cluster. We find a rich population of globular clusters and UCDs in Abell 2744. The spatial distribution of these objects is consistent with the mass map derived from lensing analysis, while showing a significant offset from the X-ray map of hot gas. The faint end of the luminosity function of the galaxies in the red sequence is fit by a flat slope, showing no faint upturn. We discuss these finding in relation with the origin of UCDs, formation of red sequence dwarf galaxies, and formation of the Pandora's cluster.
키워드