98 citations · 491 across the 29 of their papers we have counts for
30 papers
Revisiting the Optical F-corona from the Artemis II Total Solar Eclipse with RAW Data: How Far Can Consumer JPEG Images Be Trusted for Astronomical Photometry?
Kohji Tsumura, Ko Arimatsu
We reanalyze the total solar eclipse images taken with a consumer camera during the Artemis II lunar flyby, using the RAW data as ground truth for our previous analysis of the rele…
Large-scale Morphology of the Optical F-corona from a Total Solar Eclipse Observation During the Artemis II Lunar Flyby
Kohji Tsumura, Ko Arimatsu
We investigated the structure of the optical F-corona, i.e., inner zodiacal light, using a publicly released wide-field image of a total solar eclipse that was obtained during the…
An optical transient candidate of 2-second duration captured by wide-field video observations
Noriaki Arima, Mamoru Doi, Shigeyuki Sako +14
Recent time-domain surveys have revealed rapid transients that evolve on timescales of days, expanding the transient population into the short-duration regime. The tr…
A search for extragalactic fast optical transients in the Tomo-e Gozen high-cadence survey
Kakeru Oshikiri, Masaomi Tanaka, Nozomu Tominaga +15
The population of optical transients evolving within a time-scale of a few hours or a day (so-called fast optical transients, FOTs) has recently been debated extensively. In partic…
Cloud reflection modelling for impact flashes on Jupiter: A new constraint on the bulk properties of the impact objects
Ko Arimatsu, Kohji Tsumura, Fumihiko Usui +1
We investigate optical characteristics of flashes caused by impacting meter- to decameter-sized outer solar system objects on Jupiter and contributions of reflected light from surf…
JASMINE: Near-Infrared Astrometry and Time Series Photometry Science
Daisuke Kawata, Hajime Kawahara, Naoteru Gouda +86
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 Aero…
Modelling the optical energy profile of the 2021 October Jupiter impact flash
Ko Arimatsu, Kohji Tsumura, Fumihiko Usui +1
We have conducted numerical simulations to reproduce the observed optical energy profile of the 15 October 2021 (UT) impact flash on Jupiter, which was the largest and the most wel…
Video Observations of Tiny Near-Earth Objects with Tomo-e Gozen
Jin Beniyama, Shigeyuki Sako, Ryou Ohsawa +20
We report the results of video observations of tiny (diameter less than 100 m) near-Earth objects (NEOs) with Tomo-e Gozen on the Kiso 105 cm Schmidt telescope. A rotational period…
Fast optical flares from M dwarfs detected by a one-second-cadence survey with Tomo-e Gozen
Masataka Aizawa, Kojiro Kawana, Kazumi Kashiyama +18
We report a one-second-cadence wide-field survey for M-dwarf flares using the Tomo-e Gozen camera mounted on the Kiso Schmidt telescope. We detect 22 flares from M3-M5 dwarfs with…
Faint debris disk peering through superflare light echo
Ko Arimatsu, Takafumi Kamizuka
We present the detectability of strong mid-infrared (MIR) light echoes from faint debris disks illuminated by bright superflares of M-dwarf stars. Circumstellar dust grains around…
Detection of an extremely large impact flash on Jupiter by high-cadence multiwavelength observations
Ko Arimatsu, Kohji Tsumura, Fumihiko Usui +1
We report the detection of an optical impact flash on Jupiter on 15 October 2021 by a dedicated telescope, Planetary ObservatioN Camera for Optical Transient Surveys (PONCOTS), for…
Deep simultaneous limits on optical emission from FRB 20190520B by 24.4 fps observations with Tomo-e Gozen
Yuu Niino, Mamoru Doi, Shigeyuki Sako +16
We conduct 24.4~fps optical observations of repeating Fast Radio Burst (FRB) 20190520B using Tomo-e Gozen, a high-speed CMOS camera mounted on the Kiso 105-cm Schmidt telescope, si…
Discovery of the Fastest Early Optical Emission from Overluminous SN Ia 2020hvf: A Thermonuclear Explosion within a Dense Circumstellar Environment
Ji-an Jiang, Keiichi Maeda, Miho Kawabata +28
In this Letter we report a discovery of a prominent flash of a peculiar overluminous Type Ia supernova, SN 2020hvf, in about 5 hours of the supernova explosion by the first wide-fi…
Detectability of optical transients with timescales of sub-seconds
Ko Arimatsu, Kohji Tsumura, Fumihiko Usui +2
We search for optical transient sources with durations of to s using a dataset obtained in the Organized Autotelescopes for Serendipitous Event Survey (OASES)…
Relationship between Radar Cross Section and Optical Magnitude based on Radar and Optical Simultaneous Observations of Faint Meteors
Ryou Ohsawa, Akira Hirota, Kohei Morita +40
Radar and optical simultaneous observations of meteors are important to understand the size distribution of the interplanetary dust. However, faint meteors detected by high power l…
An optical search for transients lasting a few seconds
Michael W. Richmond, Masaomi Tanaka, Tomoki Morokuma +37
Using a prototype of the Tomo-e Gozen wide-field CMOS mosaic camera, we acquire wide-field optical images at a cadence of 2 Hz and search them for transient sources of duration 1.5…
Amateur telescopes discover a kilometre-sized Kuiper belt object from stellar occultation
K. Arimatsu, K. Tsumura, F. Usui +7
Kuiper belt objects (KBOs) are thought to be the remnant of the early solar system, and their size distribution provides an opportunity to explore the formation and evolution of th…
New constraint on the atmosphere of (50000) Quaoar from a stellar occultation
Ko Arimatsu, Ryou Ohsawa, George L. Hashimoto +35
We report observations of a stellar occultation by the classical Kuiper belt object (50000) Quaoar occurred on 28 June 2019. A single-chord high-cadence (2 Hz) photometry dataset w…
Luminosity Function of Faint Sporadic Meteors measured with a Wide-Field CMOS mosaic camera Tomo-e PM
Ryou Ohsawa, Shigeyuki Sako, Yuki Sarugaku +34
Imaging observations of faint meteors were carried out on April 11 and 14, 2016 with a wide-field CMOS mosaic camera, Tomo-e PM, mounted on the 105-cm Schmidt telescope at Kiso Obs…
Cold Molecular Gas Along the Merger Sequence in Local Luminous Infrared Galaxies
Takuji Yamashita, Shinya Komugi, Hideo Matsuhara +7
We present an initial result from the 12CO (J=1-0) survey of 79 galaxies in 62 local luminous and ultra-luminous infrared galaxy (LIRG and ULIRG) systems obtained using the 45 m te…
Organized Autotelescopes for Serendipitous Event Survey (OASES): design and performance
Ko Arimatsu, Kohji Tsumura, Kohei Ichikawa +7
Organized Autotelescopes for Serendipitous Event Survey (OASES) is an optical observation project that aims to detect and investigate stellar occultation events by kilometer-sized…
AKARI far-infrared maps of the zodiacal dust bands
Takafumi Ootsubo, Yasuo Doi, Satoshi Takita +6
Zodiacal emission is thermal emission from interplanetary dust. Its contribution to the sky brightness is non-negligible in the region near the ecliptic plane, even in the far-infr…
Calibration of the AKARI Far-infrared All Sky Survey Maps
Satoshi Takita, Yasuo Doi, Takafumi Ootsubo +10
We present an initial analysis of the properties of the all-sky image obtained by the Far-Infrared Surveyor (FIS) onboard the AKARI satellite, at 65~m (N60), 90~m (WIDE-S), 1…
The Far-Infrared All-Sky Survey Maps
Yasuo Doi, Satoshi Takita, Takafumi Ootsubo +15
We present a far-infrared all-sky atlas from a sensitive all-sky survey using the Japanese satellite. The survey covers % of the sky in four photometric bands centred…