Search Results - "Maehara, Hiroyuki"

Statistical Properties of Superflares on Solar-type Stars: Results Using All of the Kepler Primary Mission Data by Okamoto, Soshi, Notsu, Yuta, Maehara, Hiroyuki, Namekata, Kosuke, Honda, Satoshi, Ikuta, Kai, Nogami, Daisaku, Shibata, Kazunari

“…We report the latest statistical analyses of superflares on solar-type (G-type main-sequence; effective temperature is 5100-6000 K) stars using all of the…”
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Do Kepler Superflare Stars Really Include Slowly Rotating Sun-like Stars?-Results Using APO 3.5 m Telescope Spectroscopic Observations and Gaia-DR2 Data by Notsu, Yuta, Maehara, Hiroyuki, Honda, Satoshi, Hawley, Suzanne L., Davenport, James R. A., Namekata, Kosuke, Notsu, Shota, Ikuta, Kai, Nogami, Daisaku, Shibata, Kazunari

“…We report the latest view of Kepler solar-type (G-type main-sequence) superflare stars, including recent updates with Apache Point Observatory (APO) 3.5 m…”
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Statistical properties of superflares on solar-type stars based on 1-min cadence data by Maehara, Hiroyuki, Shibayama, Takuya, Notsu, Yuta, Notsu, Shota, Honda, Satoshi, Nogami, Daisaku, Shibata, Kazunari

“…We searched for superflares on solar-type stars using Kepler data with 1-min sampling in order to detect superflares with a short duration. We found 187…”
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Analysis of a Kepler Light Curve of the Novalike Cataclysmic Variable KIC 8751494 by Kato, Taichi, Hiroyuki, Maehara

“…We analyzed a Kepler light curve of KIC 8751494, a recently recognized novalike cataclysmic variable in the Kepler field. We detected a stable periodicity of…”
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Starspot activity and superflares on solar-type stars by Maehara, Hiroyuki, Notsu, Yuta, Notsu, Shota, Namekata, Kosuke, Honda, Satoshi, Ishii, Takako T., Nogami, Daisaku, Shibata, Kazunari

“…Abstract We analyze the correlation between starspots and superflares on solar-type stars using observations from the Kepler mission. The analysis shows that…”
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Magnitude Estimates for the Carrington Flare in 1859 September: As Seen from the Original Records by Hayakawa, Hisashi, Bechet, Sabrina, Clette, Frédéric, Hudson, Hugh S., Maehara, Hiroyuki, Namekata, Kosuke, Notsu, Yuta

“…Abstract The Carrington flare in 1859 September is a benchmark, as the earliest reported solar flare and as an event with one of the greatest terrestrial…”
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Probable detection of an eruptive filament from a superflare on a solar-type star by Namekata, Kosuke, Maehara, Hiroyuki, Honda, Satoshi, Notsu, Yuta, Okamoto, Soshi, Takahashi, Jun, Takayama, Masaki, Ohshima, Tomohito, Saito, Tomoki, Katoh, Noriyuki, Tozuka, Miyako, Murata, Katsuhiro L., Ogawa, Futa, Niwano, Masafumi, Adachi, Ryo, Oeda, Motoki, Shiraishi, Kazuki, Isogai, Keisuke, Seki, Daikichi, Ishii, Takako T., Ichimoto, Kiyoshi, Nogami, Daisaku, Shibata, Kazunari

“…Solar flares are often accompanied by filament/prominence eruptions (~10 4  K and ~10 10−11  cm −3 ), sometimes leading to coronal mass ejections that directly…”
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A Superflare on YZ Canis Minoris Observed by the Seimei Telescope and TESS: Red Asymmetry of Hα Emission Associated with White-light Emission by Namizaki, Keiichi, Namekata, Kosuke, Maehara, Hiroyuki, Notsu, Yuta, Honda, Satoshi, Nogami, Daisaku, Shibata, Kazunari

“…Abstract Active M-type stars are known to often produce superflares on the surface. Radiation from stellar (super)flares is important for exoplanet…”
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Starspot Mapping with Adaptive Parallel Tempering. II. Application to TESS Data for M-dwarf Flare Stars AU Microscopii, YZ Canis Minoris, and EV Lacertae by Ikuta, Kai, Namekata, Kosuke, Notsu, Yuta, Maehara, Hiroyuki, Okamoto, Soshi, Honda, Satoshi, Nogami, Daisaku, Shibata, Kazunari

“…Abstract Starspots and stellar flares are indicators of stellar magnetic activity. The magnetic energy stored around spots is thought to be the origin of…”
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Detection of a High-velocity Prominence Eruption Leading to a CME Associated with a Superflare on the RS CVn-type Star V1355 Orionis by Inoue, Shun, Maehara, Hiroyuki, Notsu, Yuta, Namekata, Kosuke, Honda, Satoshi, Namizaki, Keiichi, Nogami, Daisaku, Shibata, Kazunari

“…Abstract Stellar coronal mass ejections (CMEs) have recently received much attention for their impacts on exoplanets and stellar evolution. Detecting…”
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Temporal Evolution of Spatially Resolved Individual Star Spots on a Planet-hosting Solar-type Star: Kepler-17 by Namekata, Kosuke, Davenport, James R. A., Morris, Brett M., Hawley, Suzanne L., Maehara, Hiroyuki, Notsu, Yuta, Toriumi, Shin, Ikuta, Kai, Notsu, Shota, Honda, Satoshi, Nogami, Daisaku, Shibata, Kazunari

“…Star spot evolution is visible evidence of the emergence/decay of the magnetic field on a stellar surface, and it is therefore important for the understanding…”
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Optical spectroscopic observations of a symbiotic star MWC 560 in the mass accumulation phase by Ando, Kazuko, Fukuda, Naoya, Sato, Bunei, Maehara, Hiroyuki, Izumiura, Hideyuki

“…Abstract There are about a dozen symbiotic stars known to produce high-velocity jets during outbursts. MWC 560 (V694 Mon) is a symbiotic star that seems to…”
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High dispersion spectroscopy of solar-type superflare stars. II. Stellar rotation, starspots, and chromospheric activities by Notsu, Yuta, Honda, Satoshi, Maehara, Hiroyuki, Notsu, Shota, Shibayama, Takuya, Nogami, Daisaku, Shibata, Kazunari

“…We conducted high dispersion spectroscopic observations of 50 superflare stars with Subaru/HDS. These 50 stars were selected from the solar-type superflare…”
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Multiwavelength Campaign Observations of a Young Solar-type Star, EK Draconis. I. Discovery of Prominence Eruptions Associated with Superflares by Namekata, Kosuke, Airapetian, Vladimir S., Petit, Pascal, Maehara, Hiroyuki, Ikuta, Kai, Inoue, Shun, Notsu, Yuta, Paudel, Rishi R., Arzoumanian, Zaven, Avramova-Boncheva, Antoaneta A., Gendreau, Keith, Jeffers, Sandra V., Marsden, Stephen, Morin, Julien, Neiner, Coralie, Vidotto, Aline A., Shibata, Kazunari

“…Abstract Young solar-type stars frequently produce superflares, serving as a unique window into the young Sun-Earth environments. Large solar flares are…”
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Spectra of V1405 Cas at the Very Beginning Indicate a Low-mass ONeMg White Dwarf Progenitor by Taguchi, Kenta, Maeda, Keiichi, Maehara, Hiroyuki, Tajitsu, Akito, Yamanaka, Masayuki, Arai, Akira, Isogai, Keisuke, Shibata, Masaaki, Tampo, Yusuke, Kojiguchi, Naoto, Nogami, Daisaku, Kato, Taichi

“…Abstract 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…”
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Apache Point Observatory (APO)/SMARTS Flare Star Campaign Observations. I. Blue Wing Asymmetries in Chromospheric Lines during Mid-M-Dwarf Flares from Simultaneous Spectroscopic and Photometric Observation Data by Notsu, Yuta, Kowalski, Adam F., Maehara, Hiroyuki, Namekata, Kosuke, Hamaguchi, Kenji, Enoto, Teruaki, Tristan, Isaiah I., Hawley, Suzanne L., Davenport, James R. A., Honda, Satoshi, Ikuta, Kai, Inoue, Shun, Namizaki, Keiichi, Nogami, Daisaku, Shibata, Kazunari

“…Abstract We conducted the time-resolved simultaneous optical spectroscopic and photometric observations of mid-M-dwarf flare stars YZ CMi, EV Lac, and AD Leo…”
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Time-resolved spectroscopic observations of an M-dwarf flare star EV Lacertae during a flare by Honda, Satoshi, Notsu, Yuta, Namekata, Kosuke, Notsu, Shota, Maehara, Hiroyuki, Ikuta, Kai, Nogami, Daisaku, Shibata, Kazunari

“…Abstract We have performed five night spectroscopic observations of the Hα line of EV Lac with a medium wavelength resolution (R ∼ 10000) using the 2 m Nayuta…”
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Calcium-rich Transient SN 2019ehk in a Star-forming Environment: Yet Another Candidate for a Precursor of a Double Neutron-star Binary by Nakaoka, Tatsuya, Maeda, Keiichi, Yamanaka, Masayuki, Tanaka, Masaomi, Kawabata, Miho, Moriya, Takashi J., Kawabata, Koji S., Tominaga, Nozomu, Takagi, Kengo, Imazato, Fumiya, Morokuma, Tomoki, Sako, Shigeyuki, Ohsawa, Ryou, Nagao, Takashi, Jiang, Ji-an, Burgaz, Umut, Taguchi, Kenta, Uemura, Makoto, Akitaya, Hiroshi, Sasada, Mahito, Isogai, Keisuke, Otsuka, Masaaki, Maehara, Hiroyuki

“…Abstract We present optical and near-infrared observations of SN 2019ehk, which was initially reported as a Type Ib supernova (SN). We show that it evolved to…”
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X-Ray, Optical, and Near-infrared Monitoring of the New X-Ray Transient MAXI J1820+070 in the Low/Hard State by Shidatsu, Megumi, Nakahira, Satoshi, Yamada, Satoshi, Kawamuro, Taiki, Ueda, Yoshihiro, Negoro, Hitoshi, Murata, Katsuhiro L., Itoh, Ryosuke, Tachibana, Yutaro, Adachi, Ryo, Yatsu, Yoichi, Kawai, Nobuyuki, Hanayama, Hidekazu, Horiuchi, Takashi, Akitaya, Hiroshi, Saito, Tomoki, Takayama, Masaki, Ohshima, Tomohito, Katoh, Noriyuki, Takahashi, Jun, Nagayama, Takahiro, Yamanaka, Masayuki, Kawabata, Miho, Nakaoka, Tatsuya, Takagi, Seiko, Morokuma, Tomoki, Morihana, Kumiko, Maehara, Hiroyuki, Sekiguchi, Kazuhiro

“…We report X-ray, optical, and near-infrared monitoring of the new X-ray transient MAXI J1820+070 discovered with MAXI on 2018 March 11. Its X-ray intensity…”
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Morpho-kinematic Modeling of the Expanding Ejecta of the Extremely Slow Nova V1280 Scorpii by Naito, Hiroyuki, Tajitsu, Akito, Ribeiro, Valério A. R. M., Arai, Akira, Maehara, Hiroyuki, Kouzuma, Shinjirou, Iijima, Takashi, Okazaki, Atsuo T., Watanabe, Makoto, Takagi, Seiko, Watanabe, Fumitake, Sakon, Itsuki, Sadakane, Kozo

“…Abstract Knowledge of the morphology of nova ejecta is essential for fully understanding the physical processes involved in nova eruptions. We studied the 3D…”
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