Search Publications
New insights on the dynamics of satellite galaxies: Effects of the figure rotation of a host galaxy
Chiba, Masashi; Sato, Genta
We investigate a mechanism to form and keep a planar spatial distribution of satellite galaxies in the Milky Way (MW), which is called the satellite plane. It has been pointed out that the ΛCDM cosmological model hardly explains the existence of such a satellite plane, so it is regarded as one of the serious problems in the current cosmology. We 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…
Detection of the neutral iron line from the supernova remnant W 49 B with Suzaku
Katsuda, Satoru; Nobukawa, Masayoshi; Nobukawa, Kumiko K. +2 more
Recent studies of supernova remnants (SNRs) have revealed that some SNRs exhibit a neutral iron line emission at 6.4 keV. This line has been proposed to originate from the interaction of high-energy particles formed in the SNR shell with the surrounding cold matter. We searched for the neutral iron line emission in the SNR W 49 B. Significant dete…
MASTER OT J030227.28+191754.5: An unprecedentedly energetic dwarf nova outburst
Schramm, Malte; Maehara, Hiroyuki; Nogami, Daisaku +60 more
We present a detailed study of the MASTER OT J030227.28
Diffraction modelling of a 2023 March 5 stellar occultation by subkilometer-sized asteroid (98943) 2001 CC21
Arimatsu, Ko; Hirabayashi, Masatoshi; Akitaya, Hiroshi +31 more
We present an analysis of a stellar occultation event caused by a near-Earth asteroid (98943) 2001 CC21, an upcoming flyby target in the Hayabusa2 extended mission, on 2023 March 5. To determine the asteroid's shape from diffraction-affected light curves accurately, we developed a novel data-reduction technique named the Diffracted Occultation's U…
The extended halo and tidal tails of the old open cluster NGC 2112
Gao, Xinhua; Zhu, Chengyu
This paper investigates the spatial structure and tidal tails of the nearby (
Discovery of a hyperluminous quasar at z = 1.62 with Eddington ratio >3 in the eFEDS field confirmed by KOOLS-IFU on Seimei Telescope
Imanishi, Masatoshi; Ueda, Yoshihiro; Toba, Yoshiki +17 more
We report the discovery of a hyperluminous type 1 quasar (eFEDS J082826.9-013911; eFEDS J0828-0139) at
Q-band line survey observations toward a carbon-chain-rich clump in the Serpens South region
Lai, Shih-Ping; Liu, Sheng-Yuan; Nakamura, Fumitaka +17 more
We have conducted Q-band (30-50 GHz) line survey observations toward a carbon-chain emission peak in the Serpens South cluster-forming region with the extended Q-band (eQ) receiver installed on the Nobeyama 45 m radio telescope. Approximately 180 lines have been detected, including tentative detection, and these lines are attributed to 52 molecule…
Processing of hydrocarbon dust in star-forming galaxies revealed with AKARI
Oyabu, Shinki; Kaneda, Hidehiro; Murata, Katsuhiro L. +5 more
Hydrocarbon dust is one of the dominant components of interstellar dust, which mainly consists of polycyclic aromatic hydrocarbons and aliphatic hydrocarbons. While hydrocarbon dust is thought to be processed in interstellar radiation fields or shocks, detailed processing mechanisms are not completely understood yet. We investigate the processing …
Multi-epoch X-ray spectral analysis of Centaurus A: Revealing new constraints on iron emission line origins
Tanimoto, Atsushi; Bamba, Aya; Hagino, Kouichi +3 more
We conduct X-ray reverberation mapping and spectral analysis of the radio galaxy Centaurus A to uncover its central structure. We compare the light curve of the hard X-ray continuum from Swift Burst Alert Telescope observations with that of the Fe K