activity
20242026
collaborators

9 papers

astro-ph.IM2026

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…

astro-ph.SR2025

Eclipsing Stellar Flare on the Demon Star Algol Binary System Observed during the MAXI-NICER Follow-up Campaign in 2018

Kazuya Nakayama, Wataru Buz Iwakiri, Teruaki Enoto +6

Algol is a well-known eclipsing binary hosting an active and variable star that exhibits frequent stellar flares. Here, we report our pre-planned and coordinated rapid X-ray follow…

astro-ph.HE2025

Unveiling the Nature of Superorbital Modulation of SMC X-1 using NinjaSat

Chin-Ping Hu, Naoyuki Ota, Takuya Takahashi +13

We report a long-term, high-cadence timing and spectral observation of the X-ray pulsar SMC X-1 using NinjaSat, a 6U CubeSat in low-Earth orbit, covering nearly a full superorbital…

astro-ph.HE2025

Return of the Clocked Burster: Exceptionally Short Recurrence Time in GS 1826-238

Tomoshi Takeda, Toru Tamagawa, Teruaki Enoto +15

We report the discovery of an exceptionally short burst recurrence time in the well-known clocked burster GS 1826238, observed with the CubeSat X-ray observatory NinjaSat. In 20…

astro-ph.HE2025

Quasi-periodic variation during a fast X-ray outburst of a high-mass X-ray binary MAXI J0709-159 / LY CMa observed by NICER

Mutsumi Sugizaki, Tatehiro Mihara, Kohei Kobayashi +6

We report on a quasi-periodic variation at Hz during a fast X-ray outburst of a high-mass X-ray binary MAXI J0709159 / LY CMa observed by the Neutron-star interior compo…

astro-ph.HE2025

Thermonuclear superburst of MAXI J1752457 observed with NinjaSat and MAXI

Amira Aoyama, Teruaki Enoto, Takuya Takahashi +17

An uncatalogued bright X-ray transient was detected with MAXI on November 9, 2024, named MAXI J1752457. The NinjaSat X-ray observatory promptly observed the source from November…