50 citations · 205 across the 30 of their papers we have counts for
31 papers
MIDSSAR: MId Dispersion Spectrograph for Stellar Activity Research
Fumihde Iwamuro, Daisaku Nogami, Hiroyuki Maehara +8
We have developed and commissioned MIDSSAR (MId Dispersion Spectrograph for Stellar Activity Research), a novel fiber-fed, dual-band spectrograph optimized for high-cadence monitor…
A Unified Timescale Relation for Quasi-Periodic Eruptions and Repeated Nuclear Transients
Shifeng Huang, Tinggui Wang, Ning Jiang +9
Quasi-periodic eruptions (QPEs) and recurrent nuclear transients (RNTs) exhibit recurrent high-amplitude flares from galactic nuclei, yet their characteristic timescales remain poo…
SN 2023gfo: A Peculiar Type IIP Supernova with High Luminosity and Normal Plateau Duration
Riko Namba, Masayuki Yamanaka, Keiichi Maeda +9
We present near-infrared (NIR) and optical observations of the highly reddened Type IIP supernova (SN) 2023gfo in the nearby galaxy NGC 4995 ( Mpc), which reached…
JWST Spectroscopy of Type Ia Supernova 2025rbs from Maximum Light to the Nebular Phase
Lindsey A. Kwok, Stéphane Blondin, Adam A. Miller +53
We present JWST observations of the Type Ia supernova (SN Ia) 2025rbs (14.5 Mpc) at +1, +23, and +84 days after B-band maximum, spanning peak light through a wavelength-depende…
GRB 260310A/SN 2026fgk: Photometric and Spectroscopic Evolution of a Nearby GRB-Supernova and an Exceptionally Bright Afterglow at z=0.153
Brendan O'Connor, Malte Busmann, Xander J. Hall +24
The association of broad-lined Type Ic supernovae with long-duration gamma-ray bursts (GRBs) has been known for 28 years. However, only about seventy gamma-ray burst supernovae (GR…
Two years of shock interaction tracing three phases of evolution: the explosion of a Type IIn supernova, SN 2019vxm
Gitika Rameshan, Rishabh Singh Teja, D. K. Sahu +10
We present multi-wavelength photometric and optical spectroscopic observations of the long-lived interacting supernova SN 2019vxm, spanning more than two years after the explosion.…
Spectral and photometric variability of SS 433 observed with XRISM and simultaneous optical and near-infrared telescopes
Yusuke Sakai, Shinya Yamada, Yuta Okada +36
We present results from coordinated multiwavelength observations of the SS 433, obtained with XRISM, optical telescopes, and near-infrared camera during 2024 April and 2025 March.…
Peculiar SN Ic 2022esa: An explosion of a massive Wolf-Rayet star in a binary as a precursor to a BH-BH binary?
Keiichi Maeda, Hanindyo Kuncarayakti, Takashi Nagao +4
A class of supernovae (SNe) termed `SN Ic-CSM' are characterized by late-time emergence of narrow emission lines of elements formed in the oxygen core of a massive star. A popular…
SN 2023xgo: Helium-rich Type Icn or Carbon-Flash Type Ibn supernova?
Anjasha Gangopadhyay, Jesper Sollerman, Konstantinos Tsalapatas +35
We present observations of SN~2023xgo, a transitional Type Ibn/Icn supernova, from to ~days relative to the -band peak. Early spectra show C~III emission rem…
Spectral evolution of the narrow emission line components in optical during the 2022 nova eruption of U Scorpii
Katsuki Muraoka, Naoto Kojiguchi, Junpei Ito +20
There remains debate over whether the accretion disk survives or is entirely disrupted after the nova eruption. In our previous paper, Muraoka et al. (2024, PASJ, 76, 293) have pho…
Spectropolarimetry of A Nuclear Transient AT2023clx: Revealing The Geometrical Alignment between The Transient Outflow and The Nuclear Dusty Region
Kohki Uno, Keiichi Maeda, Takashi Nagao +10
AT2023clx, which occurred in NGC3799 with a Low-Ionization Nuclear Emission-Line Region (LINER), is one of the most nearby nuclear transients classified as a tidal disruption event…
Smart Kanata: A Framework for Autonomous Decision Making in Rapid Follow-up Observations of Cataclysmic Variables
Makoto Uemura, Yuzuki Koga, Ryosuke Sazaki +11
Studying the early stages of transient events provides crucial information about the fundamental physical processes in cataclysmic variables (CVs). However, determining an appropri…
Discovery of Two New Eruptions of the Ultrashort Recurrence Time Nova M31N 2017-01e
Allen W. Shafter, Jingyuan Zhao, Kamil Hornoch +15
We report the recent discovery of two new eruptions of the recurrent nova M31N 2017-01e in the Andromeda galaxy. The latest eruption, M31N 2024-08c, reached on 2024 August…
SN 2021foa: the bridge between SN IIn and Ibn
Anjasha Gangopadhyay, Naveen Dukiya, Takashi J Moriya +26
We present the long-term photometric and spectroscopic analysis of a transitioning SN~IIn/Ibn from 10.8 d to 150.7 d post -band maximum. SN~2021foa shows prominent He {\sc i}…
MASTER OT J030227.28+191754.5: an unprecedentedly energetic dwarf nova outburst
Yusuke Tampo, Taichi Kato, Keisuke Isogai +60
We present a detailed study of the MASTER OT J030227.28+191754.5 outburst in 2021-2022, reaching an amplitude of 10.2 mag and a duration of 60 d. The detections of (1) the double-p…
Unravelling the asphericities in the explosion and multi-faceted circumstellar matter of SN 2023ixf
Avinash Singh, R. S. Teja, T. J. Moriya +33
We present a detailed investigation of photometric, spectroscopic, and polarimetric observations of the Type II SN 2023ixf. Earlier studies have provided compelling evidence for a…
Optical and soft X-ray light-curve analysis during the 2022 eruption of U Scorpii: structural changes in the accretion disk
Katsuki Muraoka, Naoto Kojiguchi, Junpei Ito +52
We present our optical photometric observations of the 2022 eruption of the recurrent nova U Scorpii (U Sco) using 49,152 data points over 70 d following the optical peak. We have…
Intermediate-luminosity Type IIP SN 2021gmj: a low-energy explosion with signatures of circumstellar material
Yuta Murai, Masaomi Tanaka, Miho Kawabata +28
We present photometric, spectroscopic and polarimetric observations of the intermediate-luminosity Type IIP supernova (SN) 2021gmj from 1 to 386 days after the explosion. The peak…
The enigmatic double-peaked stripped-envelope SN 2023aew
Tuomas Kangas, Hanindyo Kuncarayakti, Takashi Nagao +29
We present optical and near-infrared photometry and spectroscopy of SN 2023aew and our findings on its remarkable properties. This event, initially resembling a Type IIb supernova…
Spectra of V1405 Cas at the very beginning indicate a low-mass ONeMg white dwarf progenitor
Kenta Taguchi, Keiichi Maeda, Hiroyuki Maehara +9
The lowest possible mass of ONeMg white dwarfs (WDs) has not been clarified despite its importance in the formation and evolution of WDs. We tackle this issue by studying the prope…
Bridging between type IIb and Ib supernovae: SN IIb 2022crv with a very thin Hydrogen envelope
Anjasha Gangopadhyay, Keiichi Maeda, Avinash Singh +26
We present optical, near-infrared, and radio observations of supernova (SN) SN~IIb 2022crv. We show that it retained a very thin H envelope and transitioned from a SN~IIb to a SN~I…
The broad-lined Type-Ic supernova SN 2022xxf with extraordinary two-humped light curves
H. Kuncarayakti, J. Sollerman, L. Izzo +60
We report on our study of supernova (SN) 2022xxf based on observations obtained during the first four months of its evolution. The light curves (LCs) display two humps of similar m…
SN 2020uem: A Possible Thermonuclear Explosion within A Dense Circumstellar Medium (I) The Nature of Type IIn/Ia-CSM SNe from Photometry and Spectroscopy
Kohki Uno, Keiichi Maeda, Takashi Nagao +18
We have performed intensive follow-up observations of a Type IIn/Ia-CSM SN (SN IIn/Ia-CSM), 2020uem, with photometry, spectroscopy, and polarimetry. In this paper, we report on the…
M31N 2017-01e: Discovery of a Previous Eruption in this Enigmatic Recurrent Nova
Allen W. Shafter, Kenta Taguchi, Jingyuan Zhao +1
We report the discovery of a previously unknown eruption of the recurrent nova M31N 2017-01e that took place on 11 January 2012. The earlier eruption was detected by Pan-STARRS and…