86 citations · 369 across the 27 of their papers we have counts for
19 papers · 1 filter
Spectroscopic and Photometric Observations of Dwarf Nova Superoutbursts by the 3.8 m Telescope Seimei and the Variable Star Network
Yusuke Tampo, Keisuke Isogai, Naoto Kojiguchi +59
We present spectroscopic and photometric observations of 17 dwarf-nova superoutbursts obtained by KOOLS-IFU mounted on the 3.8 m telescope Seimei at Okayama Observatory of Kyoto Un…
Discovery of a young low-mass brown dwarf transiting a fast-rotating F-type star by the Galactic Plane eXoplanet (GPX) survey
P. Benni, A. Y. Burdanov, V. V. Krushinsky +64
We announce the discovery of GPX-1 b, a transiting brown dwarf with a mass of and a radius of , the first sub-stell…
Multi-wavelength photometry during the 2018 superoutburst of the WZ Sge-type dwarf nova EG Cancri
Mariko Kimura, Keisuke Isogai, Taichi Kato +45
We report on the multi-wavelength photometry of the 2018 superoutburst in EG Cnc. We have detected stage A superhumps and long-lasting late-stage superhumps via the optical photome…
First Detection of Two Superoutbursts during Rebrightening Phase of a WZ Sge-type Dwarf Nova: TCP J21040470+4631129
Yusuke Tampo, Kojiguchi Naoto, Keisuke Isogai +51
We report photometric and spectroscopic observations and analysis of the 2019 superoutburst of TCP J21040470+4631129. This object showed a 9-mag superoutburst with early superhumps…
ASASSN-18fk: A new WZ Sge-type dwarf nova with multiple rebrightenings and a new candidate for a superhumping intermediate polar
E. Pavlenko, K. Niijima, P. Mason +23
We present the result of a multi-longitude campaign on the photometric study of the dwarf nova ASASSN-18fk during its superoutburst in 2018. It was observed with 18 telescopes at 1…
Cool spots on the surface of the active giant PZ Mon
Yu. V. Pakhomov, V. I. Shenavrin, N. I. Bondar' +4
Based on the multiband (BVRIJHKL) photometric observations of the active red giant PZ Mon performed for the first time in the winter season of 2017-2018, we have determined the mai…
Discovery of Standstills in the SU UMa-Type Dwarf Nova NY Serpentis
Taichi Kato, Elena P. Pavlenko, Nikolaj V. Pit +40
We found that the SU UMa-type dwarf nova NY Ser in the period gap [orbital period 0.097558(6) d] showed standstills twice in 2018. This is the first clear demonstration of a stands…
Asynchronous polar V1500 Cyg: orbital, spin and beat periods
E. P. Pavlenko, P. A. Mason, A. A. Sosnovskij +7
The bright Nova Cygni 1975 is a rare nova on a magnetic white dwarf (WD). Later it was found to be an asynchronous polar, now called V1500 Cyg. Our multisite photometric campaign o…
Spotted surface structure of the active giant PZ Mon
Yu. V. Pakhomov, K. A. Antonyuk, N. I. Bondar' +3
Based on our photometric observations in 2015-2016 and archival photometric data for the active red giant PZ Mon, we have found the main characteristics of the stellar surface: the…
Stability of an active longitude of the giant PZ Mon
Yu. V. Pakhomov, K. A. Antonyuk, N. I. Bondar' +1
Analysis of photometric data of the active giant PZ Mon is presented. Using ASAS-3 project data and new more accurate photometry we establish that during 15 years of PZ Mon CCD obs…
ASASSN-16eg: New candidate of long-period WZ Sge-type dwarf nova
Yasuyuki Wakamatsu, Keisuke Isogai, Mariko Kimura +19
We report on our photometric observations of the 2016 superoutburst of ASASSN-16eg. This object showed a WZ Sge-type superoutburst with prominent early superhumps with a period of…
OT J002656.6+284933 (CSS101212:002657+284933): An SU UMa-Type Dwarf Nova with Longest Superhump Period
Taichi Kato, Tamas Tordai, Colin Littlefield +17
We observed the 2016 outburst of OT J002656.6+284933 (CSS101212:002657+284933) and found that it has the longest recorded [0.13225(1) d in average] superhumps among SU UMa-type dwa…
Superoutburst of WZ Sge-type Dwarf Nova Below the Period Minimum: ASASSN-15po
Kosuke Namekata, Keisuke Isogai, Taichi Kato +38
We report on a superoutburst of a WZ Sge-type dwarf nova (DN), ASASSN-15po. The light curve showed the main superoutburst and multiple rebrightenings. In this outburst, we observed…
RZ Leonis Minoris Bridging between ER Ursae Majoris-Type Dwarf Nova and Novalike System
Taichi Kato, Ryoko Ishioka, Keisuke Isogai +64
We observed RZ LMi, which is renowned for the extremely (~19d) short supercycle and is a member of a small, unusual class of cataclysmic variables called ER UMa-type dwarf novae, i…
Superoutburst of CR Bootis: Estimation of Mass Ratio of a typical AM CVn star by Stage A Superhumps
Keisuke Isogai, Taichi Kato, Tomohito Ohshima +31
We report on two superoutbursts of the AM CVn-type object CR Boo in 2014 April--March and 2015 May--June. A precursor outburst acompanied both of these superoutbursts. During the r…
NY Serpentis: SU UMa-Type Nova in the Period Gap with Diversity of Normal Outbursts
Elena P. Pavlenko, Taichi Kato, Oksana I. Antonyuk +16
We present photometric study of NY Ser, an in-the-gap SU UMa-type nova, in 2002 and 2013. We determined the duration of the superoutburst and the mean superhump period to be 18 d a…
Superoutburst of SDSS J090221.35+381941.9: First Measurement of Mass Ratio in an AM CVn-Type Object using Growing Superhumps
Taichi Kato, Tomohito Ohshima, Denis Denisenko +36
We report on a superoutburst of the AM CVn-type object SDSS J090221.35+381941.9 [J0902; orbital period 0.03355(6) d] in 2014 March-April. The entire outburst consisted of a precurs…
Photometric Study of the Unusual Binary System VSX J052807.9+725606
N. A. Virnina, I. L. Andronov, K. A. Antoniuk
The results of three-color BVR photometric study of a recently discovered unusual binary system VSX J052807.9+725606 = USNO-B1.0 1629-0064825 are presented. This system is very sim…
A study of the photometric variability of the peculiar magnetic white dwarf WD1953-011
G. Valyavin, K. Antonyuk, S. Plachinda +14
We present and interpret simultaneous new photometric and spectroscopic observations of the peculiar magnetic white dwarf WD1953-011. The flux in the V-band filter and intensity of…