6 papers
Tracing the Orbital Motion of the Accreting White Dwarf in EX~Hydrae with XRISM/Resolve
Yuken Ohshiro, Yukikatsu Terada, Taichi Ichikawa +7
Measuring the masses of accreting white dwarfs (WDs) is crucial for understanding their evolution and the physics of accretion. High-resolution X-ray spectroscopy can trace the WD…
Plasma Dynamics of Radiative Cooling Accretion Flow in AM Herculis with XRISM
Yukikatsu Terada, Kaya Mori, Takayuki Hayashi +14
We present XRISM/Resolve high-resolution X-ray spectroscopy of the prototypical magnetic cataclysmic variable AM Herculis. All satellite lines of highly ionized Fe are fully resolv…
Disk instability model incorporating a variable inner disk radius in SS Cyg and U Gem
Mariko Kimura, Osaki Yoji
Previous theoretical studies indicate that the inner disk in dwarf novae evaporates into a high-temperature, optically thin, and geometrically thick accretion flow during quiescenc…
A probable inside-out dwarf nova outburst from the period bouncer candidate ASASSN-25dc
Yusuke Tampo, Naoto Kojiguchi, Mariko Kimura +13
We report optical time-resolved photometric observations of a newly-discovered outbursting system, ASASSN-25dc. Its 8-mag amplitude, 40-day duration, 1-mag dip in the outburst plat…
Spectral and photometric variability of SS 433 observed with XRISM and simultaneous optical and near-infrared telescopes
Yusuke Sakai, Shinya Yamada, Yuta Okada +36
We present results from coordinated multiwavelength observations of the SS 433, obtained with XRISM, optical telescopes, and near-infrared camera during 2024 April and 2025 March.…
Evolution of the inner accretion flow and the white-dwarf spin pulse during the 2023 outburst in GK Persei
Mariko Kimura, Takayuki Hayashi, Yuuki Wada +8
We present our X-ray and optical observations performed by NICER, NuSTAR, and Tomo-e Gozen during the 2023 outburst in the intermediate polar GK Persei. The X-ray spectrum consiste…