38 citations · 134 across the 20 of their papers we have counts for
21 papers
In-orbit Demonstration of X-ray Pulsar Navigation with NinjaSat
Naoyuki Ota, Takuya Takahashi, Toru Tamagawa +26
This study demonstrated the pulsar navigation capability of the CubeSat X-ray observatory NinjaSat, which is equipped with two Gas Multiplier Counters (GMCs). The GMCs are sensitiv…
Gamma-Ray and AntiMatter Survey(GRAMS) experiment
J. Zeng, T. Aramaki, D. Ames +62
The Gamma-Ray and AntiMatter Survey (GRAMS) is a next-generation experiment using a Liquid Argon Time Projection Chamber (LArTPC) detector to measure MeV gamma rays and antiparticl…
Pile-up simulator for XRISM/Xtend onboard the X-ray Imaging and Spectroscopy Mission (XRISM)
Tomokage Yoneyama, Tsubasa Tamba, Hirokazu Odaka +6
In X-ray astronomy, most observatories utilize multi-pixel photon-counting devices. When a photon counting device observes a bright source, we face an unavoidable problem called pi…
High count rate effects in event processing for XRISM/Resolve x-ray microcalorimeter: II. Energy scale and resolution in orbit
Misaki Mizumoto, Yoshiaki Kanemaru, Shinya Yamada +7
The Resolve instrument on the X-ray Imaging and Spectroscopy Mission (XRISM) uses a 36-pixel microcalorimeter designed to deliver high-resolution, non-dispersive X-ray spectroscopy…
The nature of spectral variability of the accreting pulsar Centaurus X-3 unveiled by NuSTAR observation covering two orbital cycles
Tsubasa Tamba, Hirokazu Odaka, Atsushi Tanimoto +3
We conducted a NuSTAR observation on the X-ray pulsar Centaurus X-3, which covered two consecutive orbital cycles of the source, including two eclipse durations. We…
Antihelium-3 Sensitivity for the GRAMS Experiment
J. Zeng, T. Aramaki, K. Aoyama +62
The Gamma-Ray and AntiMatter Survey (GRAMS) is a next-generation balloon/satellite mission utilizing a Liquid Argon Time Projection Chamber (LArTPC) detector to measure both MeV ga…
High count rate effects in event processing for XRISM/Resolve x-ray microcalorimeter: I. Ground test
Misaki Mizumoto, Tsubasa Tamba, Masahiro Tsujimoto +11
The spectroscopic performance of an X-ray microcalorimeter is compromised at high count rates. In this study, we utilize the Resolve X-ray microcalorimeter onboard the XRISM satell…
NinjaSat: Astronomical X-ray CubeSat Observatory
Toru Tamagawa, Teruaki Enoto, Takao Kitaguchi +22
NinjaSat is an X-ray CubeSat designed for agile, long-term continuous observations of bright X-ray sources, with the size of 6U ( mm) and a mass of 8 kg.…
NinjaSat monitoring of Type-I X-ray bursts from the clocked burster SRGA J144459.2604207
Tomoshi Takeda, Toru Tamagawa, Teruaki Enoto +25
The CubeSat X-ray observatory NinjaSat was launched on 2023 November 11 and has provided opportunities for agile and flexible monitoring of bright X-ray sources. On 2024 February 2…
First operation of LArTPC in the stratosphere as an engineering GRAMS balloon flight (eGRAMS)
R. Nakajima, S. Arai, K. Aoyama +60
GRAMS (Gamma-Ray and AntiMatter Survey) is a next-generation balloon/satellite experiment utilizing a LArTPC (Liquid Argon Time Projection Chamber), to simultaneously target astrop…
Imaging reconstruction method on X-ray data of CMOS polarimeter combined with coded aperture
Tsubasa Tamba, Hirokazu Odaka, Taihei Watanabe +7
X-ray polarization is a powerful tool for unveiling the anisotropic characteristics of high-energy celestial objects. We present a novel imaging reconstruction method designed for…
Development of the X-ray polarimeter using CMOS imager: polarization sensitivity of a pixel CMOS sensor
Toshiya Iwata, Kouichi Hagino, Hirokazu Odaka +10
We are developing an imaging polarimeter by combining a fine-pixel CMOS image sensor with a coded aperture mask as part of the cipher project, aiming to achieve X-ray polarimetry i…
Gas selection for Xe-based LCP-GEM detectors onboard the CubeSat X-ray observatory NinjaSat
T. Takeda, T. Tamagawa, T. Enoto +18
We present a gas selection for Xe-based gas electron multiplier (GEM) detectors, Gas Multiplier Counters (GMCs) onboard the CubeSat X-ray observatory NinjaSat. To achieve an energy…
Orbital- and spin-phase variability in the X-ray emission from the accreting pulsar Cen X-3
Tsubasa Tamba, Hirokazu Odaka, Atsushi Tanimoto +3
We analyzed 39 ks NuSTAR observation data of the high mass X-ray binary Cen X-3 in order to investigate the orbital- and spin-phase spectral variability. The observation covers the…
Simulation-based spectral analysis of X-ray CCD data affected by photon pile-up
Tsubasa Tamba, Hirokazu Odaka, Aya Bamba +6
We have developed a simulation-based method of spectral analysis for pile-up affected data of X-ray CCDs without any loss of photon statistics. As effects of the photon pile-up app…
Discovery of 40.5 ks Hard X-ray Pulse-Phase Modulations from SGR 1900+14
K. Makishima, T. Tamba, Y. Aizawa +4
X-ray timing properties of the magnetar SGR 1900+14 were studied, using the data taken with Suzaku in 2009 and NuSTAR in 2016, for a time lapse of 114 ks and 242 ks, respectively.…
Detailed Design of the Science Operations for the XRISM mission
Yukikatsu Terada, Matt Holland, Michael Loewenstein +36
XRISM is an X-ray astronomical mission by the JAXA, NASA, ESA and other international participants, that is planned for launch in 2022 (Japanese fiscal year), to quickly restore hi…
Return of the Big Glitcher: NICER timing and glitches of PSR J0537-6910
Wynn C. G. Ho, Cristobal M. Espinoza, Zaven Arzoumanian +7
PSR J0537-6910, also known as the Big Glitcher, is the most prolific glitching pulsar known, and its spin-induced pulsations are only detectable in X-ray. We present results from a…
Artifact-less Coded Aperture Imaging in the X-ray Band with Multiple Different Random Patterns
Tomoaki Kasuga, Hirokazu Odaka, Kosuke Hatauchi +7
The coded aperture imaging technique is a useful method of X-ray imaging in observational astrophysics. However, the presence of imaging noise or so-called artifacts in a decoded i…
Development of the detector simulation framework for the Wideband Hybrid X-ray Imager onboard FORCE
Hiromasa Suzuki, Tsubasa Tamba, Hirokazu Odaka +8
FORCE is a Japan-US space-based astronomy mission for an X-ray imaging spectroscopy in an energy range of 1--80 keV. The Wideband Hybrid X-ray Imager (WHXI), which is the main foca…
Temporal and spectral X-ray properties of magnetar SGR 1900+14 derived from observations with NuSTAR and XMM-Newton
Tsubasa Tamba, Aya Bamba, Hirokazu Odaka +1
X-ray observations play a crucial role in understanding the emission mechanism and relevant physical phenomena of magnetars. We report X-ray observations of a young magnetar SGR 19…