199 citations · 799 across the 26 of their papers we have counts for
26 papers
Evidence for planetary hypothesis for PTFO 8-8695b with five-year optical/infrared monitoring observations
Yuta Tanimoto, Takuya Yamashita, Takahiro Ui +16
PTFO 8-8695b (CVSO 30b) is a young planet candidate whose host star is a 2.6 Myr-old T-Tauri star, and there have been continuous discussions about the nature of this system…
Extended Optical/NIR Observations of Type Iax Supernova 2014dt: Possible Signatures of a Bound Remnant
Miho Kawabata, Koji S. Kawabata, Keiich Maeda +19
We present optical and near-infrared observations of the nearby Type Iax supernova (SN) 2014dt from 14 to 410 days after the maximum light. The velocities of the iron absorption li…
Low-luminosity Type IIP Supernova 2016bkv with early-phase circumstellar interaction
Tatsuya Nakaoka, Koji S. Kawabata, Keiichi Maeda +22
We present optical and near-infrared observations of a low-luminosity Type IIP supernova (SN) 2016bkv from the initial rising phase to the plateau phase. Our observations show that…
OISTER Optical and Near-Infrared Monitoring Observations of a Peculiar Radio-Loud Active Galactic Nucleus SDSS J110006.07+442144.3
Tomoki Morokuma, Masaomi Tanaka, Yasuyuki T. Tanaka +80
We present monitoring campaign observations at optical and near-infrared (NIR) wavelengths for a radio-loud active galactic nucleus (AGN) at z=0.840, SDSS~J110006.07+442144.3 (here…
Systematic Study of Gamma-ray bright Blazars with Optical Polarization and Gamma-ray Variability
Ryosuke Itoh, Krzysztof Nalewajko, Yasushi Fukazawa +18
Blazars are highly variable active galactic nuclei which emit radiation at all wavelengths from radio to gamma-rays. Polarized radiation from blazars is one key piece of evidence f…
Multifrequency Photo-polarimetric WEBT Observation Campaign on the Blazar S5 0716+714: Source Microvariability and Search for Characteristic Timescales
G. Bhatta, Ł. Stawarz, M. Ostrowski +43
Here we report on the results of the WEBT photo-polarimetric campaign targeting the blazar S5~0716+71, organized in March 2014 to monitor the source simultaneously in BVRI and near…
X-ray and Optical Correlation of Type I Seyfert NGC 3516 Studied with Suzaku and Japanese Ground-Based Telescopes
Hirofumi Noda, Takeo Minezaki, Makoto Watanabe +23
From 2013 April to 2014 April, we performed an X-ray and optical simultaneous monitoring of the type 1.5 Seyfert galaxy NGC 3516. It employed Suzaku, and 5 Japanese ground-based te…
OISTER Optical and Near-Infrared Observations of the Super-Chandrasekhar Supernova Candidate SN 2012dn: Dust Emission from the Circumstellar Shell
Masayuki Yamanaka, Keiichi Maeda, Masaomi Tanaka +34
We present extensively dense observations of the super-Chandrasekhar supernova (SC SN) candidate SN 2012dn from to days after the date of its -band maximum in the o…
Polarization angle swings in blazars: The case of 3C 279
S. Kiehlmann, T. Savolainen, S. G. Jorstad +61
Over the past few years, several occasions of large, continuous rotations of the electric vector position angle (EVPA) of linearly polarized optical emission from blazars have been…
No Evidence of Intrinsic Optical/Near-Infrared Linear Polarization for V404 Cygni During its Bright Outburst in 2015: Broadband Modeling and Constraint on Jet Parameters
Y. T. Tanaka, R. Itoh, M. Uemura +39
We present simultaneous optical and near-infrared (NIR) polarimetric results for the black hole binary V404 Cygni spanning the duration of its 7-day long optically-brightest phase…
Optical and Near-Infrared Polarimetry for a Highly Dormant Comet 209P/LINEAR
Daisuke Kuroda, Masateru Ishiguro, Makoto Watanabe +24
We conducted an optical and near-infrared polarimetric observation of the highly dormant Jupiter-Family Comet, 209P/LINEAR. Because of its low activity, we were able to determine t…
Discovery of a Highly Polarized Optical Microflare in the Blazar S5 0716+714 During 2014 WEBT Campaign
Gopal Bhatta, Arti Goyal, Michal Ostrowski +42
The occurrence of low-amplitude flux variations in blazars on hourly timescales, commonly known as microvariability, is still a widely debated subject in high-energy astrophysics.…
Type IIb Supernova 2013df Entering Into An Interaction Phase: A Link between the Progenitor and the Mass Loss
K. Maeda, T. Hattori, D. Milisavljevic +23
We report the late-time evolution of Type IIb Supernova (SN IIb) 2013df. SN 2013df showed a dramatic change in its spectral features at ~1 year after the explosion. Early on it sho…
OISTER Optical and Near-Infrared Observations of Type Iax Supernova 2012Z
Masayuki Yamanaka, Keiichi Maeda, Koji S. Kawabata +30
We report observations of the Type Iax supernova (SN Iax) 2012Z at optical and near-infrared wavelengths from immediately after the explosion until days after the maxi…
Probing the nature of the TeV gamma-ray binary HESS J0632+057 by monitoring Be disk variability
Yuki Moritani, Atsuo T. Okazaki, Alex C. Carciofi +9
We report on monitoring observations of the TeV gamma-ray binary HESS J0632+057, which were carried out to constrain the interaction between the Be circumstellar disk and the compa…
Rapid Variability of Blazar 3C 279 during Flaring States in 2013-2014 with Joint Fermi-LAT, NuSTAR, Swift, and Ground-Based Multi-wavelength Observations
M. Hayashida, K. Nalewajko, G. M. Madejski +49
We report the results of a multi-band observing campaign on the famous blazar 3C 279 conducted during a phase of increased activity from 2013 December to 2014 April, including firs…
Kanata optical and X-ray monitoring of Gamma-ray emitting Narrow-Line Seyfert 1 and Radio galaxies
Kenji Kawaguchi, Yasushi Fukazawa, Yasuyuki Tanaka +6
Broadband spectrum of AGN consists of multiple components such as jet emission and accretion disk emission. Temporal correlation study is useful to understand emission components a…
An emergence of new polarized emission region in blazar Mrk 421 associated with X-ray flare
Ryosuke Itoh, Yasushi Fukazawa, Yasuyuki T. Tanaka +8
We report on long-term multi-wavelength monitoring of blazar Mrk~421 from 2010 to 2011. The source exhibited extreme X-ray flares in 2010. Our research group performed optical phot…
Discovery of Dramatic Optical Variability in SDSS J1100+4421: A Peculiar Radio-Loud Narrow-Line Seyfert 1 Galaxy?
Masaomi Tanaka, Tomoki Morokuma, Ryosuke Itoh +55
We present our discovery of dramatic variability in SDSS J1100+4421 by the high-cadence transient survey Kiso Supernova Survey (KISS). The source brightened in the optical by at le…
Kiso Supernova Survey (KISS): Survey Strategy
Tomoki Morokuma, Nozomu Tominaga, Masaomi Tanaka +58
The Kiso Supernova Survey (KISS) is a high-cadence optical wide-field supernova (SN) survey. The primary goal of the survey is to catch the very early light of a SN, during the sho…
Optical and Near-Infrared Polarimetry of Highly Reddened Type Ia Supernova 2014J: Peculiar Properties of Dust in M82
K. S. Kawabata, H. Akitaya, M. Yamanaka +46
We presented optical and near-infrared multi-band linear polarimetry of the highly reddened Type Ia SN~2014J appeared in M82. SN~2014J exhibits large polarization at shorter wavele…
Variable optical polarization during high state in gamma-ray loud narrow line Seyfert 1 galaxy 1H 0323+342
Ryosuke Itoh, Yasuyuki T. Tanaka, Hiroshi Akitaya +34
We present results of optical polarimetric and multi-band photometric observations for gamma-ray loud narrow-line Seyfert 1 galaxy 1H 0323+342. This object has been monitored by 1.…
Early-phase photometry and spectroscopy of transitional Type Ia SN 2012ht: Direct constraint on the rise time
Masayuki Yamanaka, Keiichi Maeda, Miho Kawabata +15
We report photometric and spectroscopic observations of the nearby Type Ia Supernova (SN Ia) 2012ht from days to days after -band maximum. The decline rate of th…
Minute-Scale Rapid Variability of Optical Polarization in Narrow-Line Seyfert 1 Galaxy: PMN J0948+0022
Ryosuke Itoh, Yasuyuki T. Tanaka, Yasushi Fukazawa +12
We report on optical photopolarimetric results of the radio-loud narrow line Seyfert 1 (RL-NLSy1) galaxy PMN J0948+0022 on 2012 December to 2013 February triggered by flux enhancem…