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arXiv · 2309.14830

GALAXY CRUISE: Spiral and ring classifications for bright galaxies at z=0.01-0.3

Rhythm Shimakawa·Masayuki Tanaka·Kei Ito·Makoto Ando
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Abstract

This paper presents a morphology classification catalog of spiral and ring features of 59,854 magnitude-limited galaxies ($r<17.8$ mag, and additional 628,005 subsamples down to $r=20$ mag) at $z=0.01-0.3$ based on the Third Public Data Release of the Hyper Suprime-Cam Subaru Strategic Program. We employ two deep learning classifiers to determine the spiral and ring structures separately based on GALAXY CRUISE Data Release 1, which is dedicated to Hyper Suprime-Cam data. The number of spiral and ring galaxies contain 31,864 and 8,808 sources, respectively, which constitute 53\% and 15\% of the sample. A notable result of this study is the construction of a large sample of ring galaxies utilizing high-quality imaging data delivered by the Subaru Hyper Suprime-Cam. However, the accurate identification of ring galaxies remains difficult at a limited seeing resolution. Additionally, we confirm that most spiral galaxies are located on the star-forming main sequence, whereas ring galaxies preferentially reside in the green valley at stellar mass of $10^{10.5}-10^{11}$ solar mass. Furthermore, decreasing fractions of spiral and ring galaxies are observed toward the centers of the galaxy clusters. The obtained morphology catalog is publicly available on the GALAXY CRUISE website.

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Rhythm Shimakawa, Masayuki Tanaka, Kei Ito, Makoto Ando. 2023-09-26. GALAXY CRUISE: Spiral and ring classifications for bright galaxies at z=0.01-0.3. https://arxiv.org/abs/2309.14830

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