Masahiro Tsujimoto Misaki Mizumoto Ken Ebisawa Hirokazu Odaka Qazuya Wada
Astrophysical Journal 960(1) 2024年1月
Supersoft X-ray sources (SSSs) are white dwarf (WD) binaries that radiate almost entirely below ∼1 keV. Their X-ray spectra are often complex when viewed with the X-ray grating spectrometers, where numerous emission and absorption features are int...
Mayu Tominaga Masahiro Tsujimoto Ken Ebisawa Teruaki Enoto Kimitake Hayasaki
Astrophysical Journal 958(1) 2023年11月
Circinus X-1 (Cir X-1) is a neutron star binary with an elliptical orbit of 16.6 days. The source is unique for its extreme youth, providing a key to understanding early binary evolution. However, its X-ray variability is too complex to reach a cl...
R. Imamura H. Awaki M. Tsujimoto S. Yamada F. S. Porter C. A. Kilbourne R. L. Kelley Y. Takei
Journal of Low Temperature Physics 211(5-6) 426-433 2023年6月
Low-temperature detectors often use mechanical coolers as part of the cooling chain in order to reach sub-Kelvin operating temperatures. The microphonic noise caused by the mechanical coolers is a general and inherent issue for these detectors. We...
Tomoki Omama Masahiro Tsujimoto Ken Ebisawa Misaki Mizumoto
Astrophysical Journal 945(2) 2023年3月
MAXI J1820+070 is a transient black hole binary discovered on 2018 March 11. The unprecedented rich statistics brought by the NICER X-ray telescope allow detailed timing analyses up to ∼1 kHz uncompromised by photon shot noise. To estimate the tim...
PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN 75(1) 177-186 2023年2月
gamma Cas analog sources are a subset of Be stars that emit intense and hard X-ray emission. Two competing ideas for their X-ray production mechanism are (a) the magnetic activities of the Be star and its disk and (b) the accretion from the Be sta...
Hiromi Seta Makoto S. Tashiro Yukikatsu Terada Yuya Shimoda Kaori Onda Yoshitaka Ishisaki Masahiro Tsujimoto Toshishige Hagihara Yoh Takei Kazuhisa Mitsuda Kevin R. Boyce Andrew E. Szymkowiak
AIP Conference Proceedings 1185 278-281 2009年12月
A digital signal processing system for the X-ray microcalorimeter array (SXS) is being developed for the next Japanese X-ray astronomy satellite, ASTRO-H. The SXS digital signal processing system evaluates each pulse by an optimal filtering proces...
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