362 citations · 939 across the 46 of their papers we have counts for
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Multiband Optical Photometric and Spectroscopic Monitoring of the 2024 Flare Event in Transition Blazar OP313
TianFang Zhang, Mitsuru Kokubo, Mamoru Doi +19
Blazars are active galactic nuclei known for their extreme variability, offering unique opportunities to study jet physics and high-energy emission mechanisms. In 2024, the Flat Sp…
A Joint Search for the Electromagnetic Counterpart to the Gravitational-Wave Binary Black-Hole Merger Candidate S250328ae with the Dark Energy Camera and the Prime Focus Spectrograph
Haibin Zhang, Mitsuru Kokubo, Sean MacBride +20
The first detection of an optical counterpart to a gravitational wave signal revealed that collaborative efforts between instruments with different specializations provide a unique…
A systematic search for rapid transients in the Subaru HSC-SSP transient survey
Seiji Toshikage, Masaomi Tanaka, Naoki Yasuda +9
Recent high-cadence transient surveys have discovered rapid transients whose light curve timescales are shorter than those of typical supernovae. In this paper, we present a system…
Optical Variability of Blazars in the Tomo-e Gozen Northern Sky Transient Survey
TianFang Zhang, Mamoru Doi, Mitsuru Kokubo +14
We studied the optical variability of 241 BL Lacs and 83 flat-spectrum radio quasars (FSRQ) from the 4LAC catalog using data from the Tomo-e Gozen Northern Sky Transient Survey, wi…
X-ray Winds In Nearby-to-distant Galaxies (X-WING) - I: Legacy Surveys of Galaxies with Ultrafast Outflows and Warm Absorbers in -
Satoshi Yamada, Taiki Kawamuro, Misaki Mizumoto +10
As an inaugural investigation under the X-ray Winds In Nearby-to-distant Galaxies (X-WING) program, we assembled a dataset comprising 132 active galactic nuclei (AGNs) spanning red…
Rayleigh and Raman scattering cross-sections and phase matrices of the ground-state hydrogen atom, and their astrophysical implications
Mitsuru Kokubo
We present explicit expressions for Rayleigh and Raman scattering cross-sections and phase matrices of the ground state hydrogen atom based on the Kramers-Heisenberg dispersio…
eROSITA Final Equatorial-Depth Survey (eFEDS): eFEDS X-ray view of WERGS Radio Galaxies selected by the Subaru/HSC and VLA/FIRST survey
Kohei Ichikawa, Takuji Yamashita, Andrea Merloni +19
We construct the eROSITA X-ray catalog of radio galaxies discovered by the WERGS survey that is made by the cross-matching of the wide-area Subaru/HSC optical survey and VLA/FIRST…
Narrow Fe-K Reverberation Mapping Unveils the Deactivated Broad-Line Region in a Changing-Look Active Galactic Nucleus
Hirofumi Noda, Taisei Mineta, Takeo Minezaki +11
"Changing-look active galactic nuclei" (CLAGNs) are known to change their apparent types between types 1 and 2, usually accompanied by a drastic change in their luminosity on times…
MUSSES2020J: The Earliest Discovery of a Fast Blue Ultraluminous Transient at Redshift 1.063
Ji-an Jiang, Naoki Yasuda, Keiichi Maeda +22
In this Letter, we report the discovery of an ultraluminous fast-evolving transient in rest-frame UV wavelengths, MUSSES2020J, soon after its occurrence by using the Hyper Suprime-…
Multiple giant eruptions and X-ray emission in the recoiling AGN/LBV candidate SDSS1133
Mitsuru Kokubo
We present a comprehensive analysis of 20 years worth of multi-color photometric light curves, multi-epoch optical spectra, and X-ray data of an off-nuclear variable object SDSS113…
Constraints on the rate of supernovae lasting for more than a year from Subaru/Hyper Suprime-Cam
Takashi J. Moriya, Ji-an Jiang, Naoki Yasuda +15
Some supernovae such as pair-instability supernovae are predicted to have the duration of more than a year in the observer frame. To constrain the rates of supernovae lasting for m…
Rapidly Evolving Transients from the Hyper Suprime-Cam SSP Transient Survey
Yusuke Tampo, Masaomi Tanaka, Keiichi Maeda +9
Rapidly evolving transients form a new class of transients which show shorter timescales of the light curves than those of typical core-collapse and thermonuclear supernovae. We pe…
A Long-Duration Luminous Type IIn Supernova KISS15s: Strong Recombination Lines from the Inhomogeneous Ejecta-CSM Interaction Region and Hot Dust Emission from Newly Formed Dust
Mitsuru Kokubo, Kazuma Mitsuda, Tomoki Morokuma +7
We report the discovery of an SN1988Z-like type IIn supernova KISS15s found in a low-mass star-forming galaxy at redshift z=0.038 during the course of the Kiso Supernova Survey (KI…