XRISM/Xtend Transient Search (XTS) detected an X-ray flare or outburst from RX J0101.0-7206
ATel #17747; M. Yoshimoto (Ehime U.), T. Yoneyama (JAXA), Y. Kanemaru, Y. Omiya, Y. Uchida (JAXA), M. Audard (U. de Geneve), E. Behar (Technion), K. Fukushima (TUS), T. Hakamata (UOsaka), S. Inoue (Kyoto U.), Y. Ishihara (Chuo U.), C. Kang (Ehime U.), T. Kiyomoto (Saitama U.), T. Kohmura (TUS), H. Kuramoto (UOsaka), J. Kurashima (U. of Miyazaki), Y. Maeda (JAXA), H. Matsumoto (UOsaka), A. Miyamoto (UOsaka), M. Mizumoto (UTEF), K. Mori (U. of Miyazaki), Y. Motogami (Saitama U.), T. Narita (RIKEN), M. Nobukawa (NUE), H. Noda (Tohoku U.), S. Ogawa (TUS), Y. Sakamoto (Tohoku U.), M. Shidatsu (Ehime U.), H. Takahashi (Hiroshima U.), T. Takagi (Ehime U.), S. Takatsuka (UOsaka), F. Takisawa (Ehime U.), Y. Terada (Saitama U., JAXA), Y. Terashima (Ehime U.), Y. Tsuboi (Chuo U.), H. Uchida (Kyoto U.), A. Yoshimoto (NWU)
on 10 Apr 2026; 07:25 UT
Credential Certification: Tomokage Yoneyama (tyoneyama263@g.chuo-u.ac.jp)
Subjects: X-ray, Binary, Transient, Pulsar
XRISM/Xtend Transient Search (XTS) detected an X-ray flare flare or outburst from an X-ray source XRISM J0101-7207 on 2026-04-09 TT. The source position is determined to be (R.A., Dec.) = (15.255, -72.114), with a systematic error of ∼ 40 arcsec.
A likely candidate is Be/X-ray binary pulsar RX J0101.0-7206, which is located ∼ 5 arcsec apart from the position of XRISM J0101-7207.
The count rate started to increase from its quiescent state on 2026-04-09 at ∼ 10:03 TT, and reached its peak at ∼ 11:26 TT with one order of magnitude high count rate than that in the quiescent.
Since then, the count rate has remained more than three times higher than the quiescent level, indicating that this object may be in an active phase.
The averaged spectrum is reproduced with an absorbed power-law model, with an absorption value of < 3 × 1021 cm -2 and a photon index of 0.8.
The peak flux is calculated as ∼ 1 × 10-11 erg s-1 cm-2 (0.4 – 10.0 keV). A systematic error of roughly 20% should be added to the statistical error. The corresponding luminosity is 5 × 1036 erg s-1 by assuming the distance to XRISM J0101-7207 of 62 kpc.
We derived the above systematic error for the flux by comparing our derived values for the sources detected with XTS in several observations with those for the corresponding X-ray counterparts. We estimated the systematic error for the source position from the separations between the detected sources with the corresponding counterparts in the same field of view.
