Search Publications
Census for the rest-frame optical and UV morphologies of galaxies at z = 4-10: First phase of inside-out galaxy formation
Ono, Yoshiaki; Ouchi, Masami; Harikane, Yuichi +7 more
We present the rest-frame optical and UV surface brightness (SB) profiles for 149 galaxies with Mopt < -19.4 mag at z = 4-10 (29 of which are spectroscopically confirmed with JWST NIRSpec), securing high signal-to-noise ratios of 10-135 with deep JWST NIRCam 1-$5\, \mu$m images obtained by the CEERS survey. We derive morphologies of …
Giant molecular clouds and their type classification in M 74: Toward understanding star formation and cloud evolution
Kobayashi, Masato I. N.; Tokuda, Kazuki; Tachihara, Kengo +10 more
We investigated the giant molecular clouds (GMCs) in M 74 (NGC 628), using data obtained from the PHANGS (Physics at High Angular resolution in Nearby GalaxieS) project. We applied GMC types according to the activity of star formation: Type I without star formation, Type II with H
Crimson Behemoth: A massive clumpy structure hosting a dusty AGN at z=4.91
Casey, Caitlin M.; Kartaltepe, Jeyhan S.; Koekemoer, Anton M. +40 more
The current paradigm for the co-evolution of galaxies and their supermassive black holes postulates that dust-obscured active galactic nuclei (AGNs) represent a transitional phase towards a more luminous and unobscured state. However, our understanding of dusty AGNs and their host galaxies at early cosmic times is inadequate due to observational l…
Low abundances of TiO and VO on the dayside of KELT-9 b: Insights from ground-based photometric observations
Ikuta, Kai; Fukui, Akihiko; Narita, Norio +21 more
We present ground-based photometric observations of secondary eclipses of the hottest known planet KELT-9 b using MuSCAT2 and Sinistro. We detect secondary eclipse signals in i and
12CO and 13CO observation of the low-metallicity dwarf galaxy DDO 154
Komugi, Shinya; Inaba, Miku; Shindou, Tetsuo
The conversion factor from carbon monoxide (CO) intensity to molecular gas mass is a source of large uncertainty in understanding gas and its relation to star formation in galaxies. In particular, the conversion factor in low-metallicity environments have remained elusive, as currently only two galaxies have been detected in any CO isotopes in env…
Third data release of the Hyper Suprime-Cam Subaru Strategic Program
Ono, Yoshiaki; Ouchi, Masami; Harikane, Yuichi +64 more
This paper presents the third data release of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP), a wide-field multi-band imaging survey with the Subaru 8.2 m telescope. HSC-SSP has three survey layers (Wide, Deep, and UltraDeep) with different area coverages and depths, designed to address a wide array of astrophysical questions. This third…
Using 3D and 2D analysis for analyzing large-scale asymmetry in galaxy spin directions
Shamir, Lior
The nature of galaxy spin is still not fully known. Iye, Yagi, and Fukumoto (2021, AJ, 907, 123) applied a 3D analysis to a dataset of bright SDSS galaxies that was used in the past for photometric analysis. They showed that the distribution of spin directions of spiral galaxies is random, providing a dipole axis with low statistical significance …
X-ray selected narrow-line active galactic nuclei in the COSMOS field: Nature of optically dull active galactic nuclei
Murayama, Takashi; Fitriana, Itsna K.
X-ray emission detection in a galaxy is one of the efficient tools for selecting active galactic nuclei (AGNs). However, many X-ray-selected AGNs are not easily selected as AGNs by their optical emission. These galaxies, so-called optically dull (OD) AGNs, are fascinating since their X-ray emission is bright even though the AGN signature in the op…
Deblurring galaxy images with Tikhonov regularization on magnitude domain
Takeuchi, Tsutomu T.; Murata, Kazumi
We propose a regularization-based deblurring method that works efficiently for galaxy images. The spatial resolution of a ground-based telescope is generally limited by seeing conditions and is much worse than space-based telescopes. This circumstance has generated considerable research interest in the restoration of spatial resolution. Since imag…
Cloud-cloud collisions and triggered star formation
Inoue, Tsuyoshi; Tachihara, Kengo; Fukui, Yasuo +2 more
Star formation is a fundamental process for galactic evolution. One issue over the last several decades has been determining whether star formation is induced by external triggers or self-regulated in a closed system. The role of an external trigger, which can effectively collect mass in a small volume, has attracted particular attention in connec…