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The Galaxy Luminosity Functions down to M~-10 in the Hydra I Cluster

H. Yamanoi·M. Tanaka·M. Hamabe·M. Yagi·S. Okamura·M. Iye·K. Shimasaku·M. Doi·Y. Komiyama·H. Furusawa
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Abstract

We study the galaxy population in the central region and a region about 0.6 Mpc away from the center of the Hydra I cluster in B- and Rc-bands down to M~-10 using the Subaru Suprime-Cam photometry. We find that the luminosity function of the entire population has a slightly steeper slope (alpha~-1.6) in the range of -20 -14) increases in the cluster center as well as bright galaxies. The Hydra I cluster is dominated by red dwarfs and the luminosity function shows a significant upturn at M~-16 as is seen in several other nearby clusters, but not in the field. This upturn and the variation in the faint-end slope of the luminosity function may be caused by the cluster environment or the evolution history of individual clusters.

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H. Yamanoi, M. Tanaka, M. Hamabe, M. Yagi, S. Okamura, M. Iye, K. Shimasaku, M. Doi, Y. Komiyama, H. Furusawa. 2007-01-24. The Galaxy Luminosity Functions down to M~-10 in the Hydra I Cluster. https://doi.org/10.1086/518475

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