137 citations · 752 across the 31 of their papers we have counts for
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Solar Neutrino Flux Fluctuations Caused by Solar Gravity Modes
Yoshiki Hatta, Yuuki Nakano, Sho Sugama +3
We have evaluated fluctuations in neutrino fluxes caused by solar gravity (g) modes based on the analysis of linear adiabatic oscillation of a spherically symmetric star. We find t…
X-ray emission of F-type stars and its analogy with G-type stars
Takuma Shimura, Ikuyuki Mitsuishi, Masanobu Kunitomo +3
We conducted a systematic spectral study for single F-type main-sequence (MS) stars without significant X-ray outbursts to investigate X-ray spectral properties such as temperature…
Solar models with protosolar accretion and turbulent mixing
Masanobu Kunitomo, Gaël Buldgen, Tristan Guillot
(abridged) Recent analyses have reported low lithium but high beryllium abundances on the solar surface; however, standard solar models (SSMs) predict Li abundances that are ~30…
The Future of Solar modelling: requirements for a new generation of solar models
Gael Buldgen, Gloria. Canocchi, Arthur. Le Saux +22
Helioseismology and solar modelling have enjoyed a golden era thanks to decades-long surveys from ground-based networks such as for example GONG, BiSON, IRIS and the SOHO and SDO s…
Spin-down of solar-mass protostars in magnetospheric accretion paradigm
Shinsuke Takasao, Masanobu Kunitomo, Takeru K. Suzuki +2
Stellar spin is one of the fundamental quantities that characterize a star itself and its planetary system. Nevertheless, stellar spin-down mechanisms in protostellar and pre-main-…
Evidence of a signature of planet formation processes from solar neutrino fluxes
Masanobu Kunitomo, Tristan Guillot, Gaël Buldgen
Solar evolutionary models are thus far unable to reproduce spectroscopic, helioseismic, and neutrino constraints consistently, resulting in the so-called solar modeling problem. In…
Diagnosing FUor-like Sources: The Parameter Space of Viscously Heated Disks in the Optical and Near-IR
Hanpu Liu, Gregory J. Herczeg, Doug Johnstone +8
FU Ori type objects (FUors) are decades-long outbursts of accretion onto young stars that are strong enough to viscously heat disks so that the disk outshines the central star. We…
Investigation of coronal properties of X-ray bright G-dwarf stars based on the solar surface magnetic field -- corona relation
Shinsuke Takasao, Ikuyuki Mitsuishi, Takuma Shimura +4
We investigated the coronal properties of G-dwarf stars including the Sun over a wide range of X-ray luminosity ( to …
Four New Self-lensing Binaries from Kepler: Radial Velocity Characterization and Astrophysical Implications
Kento Masuda, Hajime Kawahara, David W. Latham +5
In Kawahara et al. (2018) and Masuda et al. (2019), we reported the discovery of four self-lensing binaries consisting of F/G-type stars and (most likely) white dwarfs whose masses…
Self-lensing Discovery of a White Dwarf in an Unusually Wide Orbit Around a Sun-like Star
Kento Masuda, Hajime Kawahara, David W. Latham +4
We report the discovery of the fifth self-lensing binary in which a low-mass white dwarf (WD) gravitationally magnifies its 15th magnitude G-star companion, KIC 8145411, during ecl…
Revisiting the pre-main-sequence evolution of stars II. Consequences of planet formation on stellar surface composition
Masanobu Kunitomo, Tristan Guillot, Shigeru Ida +1
We want to investigate how planet formation is imprinted on stellar surface composition using up-to-date stellar evolution models. We simulate the evolution of pre-main-sequence st…
Revisiting the pre-main-sequence evolution of stars I. Importance of accretion efficiency and deuterium abundance
Masanobu Kunitomo, Tristan Guillot, Taku Takeuchi +1
Recent theoretical work has shown that the pre-main-sequence (PMS) evolution of stars is much more complex than previously envisioned. Instead of the traditional steady, one-dimens…
From Birth to Death of Protoplanetary Disks: Modeling Their Formation, Evolution, and Dispersal
Shigeo S. Kimura, Masanobu Kunitomo, Sanemichi Z. Takahashi
Formation, evolution, and dispersal processes of protoplanetary disks are investigated and the disk lifetime is estimated. Gravitational collapse of a pre-stellar core forms both a…