Search Publications
Detection of the [O I] 63 µm emission line from the z = 6.04 quasar J2054-0005
Fujimoto, Seiji; Inoue, Akio K.; Hashimoto, Takuya +23 more
We report the highest-redshift detection of [O I] 63
Revisiting the Suzaku spectrum of the Galactic SNR W 49B: Non-detection of iron K-shell charge-exchange emission and refined ejecta-mass ratios of iron-group elements
Sato, Toshiki; Sawada, Makoto; Maeda, Keiichi +1 more
The origin of the recombining plasma in several Galactic SNRs has been debated. A plausible mechanism would be a rapid cooling in the past, by either an adiabatic or a conductive process. A recent spectral study of W 49B reported a possible charge-exchange emission due to collisions between the shock-heated ejecta and cold clouds, which could be d…
Smart Kanata: A framework for autonomous decision-making in rapid follow-up observations of cataclysmic variables
Maehara, Hiroyuki; Nogami, Daisaku; Uemura, Makoto +11 more
Studying the early stages of transient events provides crucial information about the fundamental physical processes in cataclysmic variables (CVs). However, determining an appropriate observation mode immediately after the discovery of a new transient presents challenges due to significant uncertainties regarding its nature. We developed a framewo…
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 …
ALMA 2D super-resolution imaging of Taurus-Auriga protoplanetary disks: Probing statistical properties of disk substructures
Tamura, Motohide; Yamaguchi, Masayuki; Nomura, Hideko +6 more
In the past decade, ALMA observations of protoplanetary disks revealed various substructures including gaps and rings. Their origin of substructures may be probed through statistical studies of their physical properties. We present the analyses of archival ALMA Band 6 continuum data of 43 disks (39 Class II and four Herbig Ae) in the Taurus-Auriga…
JASMINE: Near-infrared astrometry and time-series photometry science
Ouchi, Masami; Isobe, Naoki; Notsu, Yuta +86 more
The Japan Astrometry Satellite Mission for INfrared Exploration (JASMINE) is a planned M-class science space mission by the Institute of Space and Astronautical Science, the Japan Aerospace Exploration Agency. JASMINE has two main science goals. One is Galactic archaeology with a Galactic Center survey, which aims to reveal the Milky Way's central…
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
The Milky Way tomography with Subaru Hyper Suprime-Cam. I. Halo substructures
Komiyama, Yutaka; Takada, Masahiro; Tanaka, Masayuki +7 more
We analyze the photometric data in the Wide layer of the Hyper Suprime-Cam Subaru Strategic Program (HSC-SSP) over ~1200 deg2 to uncover new halo substructures beyond the distance, D⊙ ~ 30 kpc, from the Sun. For this purpose, we develop an isochrone filter for an old, metal-poor stellar system to extract the faint main-sequen…
A kinematic analysis of the giant molecular complex W3: Possible evidence for cloud-cloud collisions that triggered OB star clusters in W3 Main and W3(OH)
Bieging, John H.; Tachihara, Kengo; Fukui, Yasuo +6 more
W3 is one of the most outstanding regions of high-mass star formation in the outer solar circle, and includes two active star-forming clouds: W3 Main and W3(OH). Based on a new analysis of the
Hitomi HXT deconvolution imaging of the Crab Nebula dazzled by the Crab pulsar
Maeda, Yoshitomo; Ishida, Manabu; Awaki, Hisamitsu +3 more
We develop a new deconvolution method to recover the precise Crab Nebula image taken by the Hitomi HXT, suppressing the artifact due to the bright Crab pulsar. We extend the Richardson-Lucy method, introducing two components corresponding to the nebula and pulsar with regularization for smoothness and flux, respectively, and performing simultaneou…