XRISM/Xtend Transient Search (XTS) detected an X-ray flare from XRISM J0602-4006
ATel #17785; M. Yoshimoto (Ehime U.), Y. Terada (Saitama U., JAXA), Y. Kanemaru, A. Miyamoto, Y. Omiya, Y. Uchida, T. Yoneyama (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), Y. Maeda (JAXA), H. Matsumoto (UOsaka), A. Miyamoto (UOsaka), M. Mizumoto (UTEF), 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. Terashima (Ehime U.), Y. Tsuboi (Chuo U.), H. Uchida (Kyoto U.), A. Yoshimoto (NWU)
on 9 May 2026; 14:45 UT
Credential Certification: Yukikatsu Terada (terada@mail.saitama-u.ac.jp)
Subjects: X-ray, Star, Transient
XRISM/Xtend Transient Search (XTS) detected an X-ray flare from an X-ray source XRISM J0602-4006 on 2026-05-08 TT. The source position is determined to be (R.A., Dec.) = (90.551, -40.105), with a systematic error of ∼ 40 arcsec. A plausible counterpart is the star UCAC2 14546266 with a distance of ∼ 1.3 kpc, which corresponds to an X-ray source 2CXO J060212.4-400619. UCAC2 14546266 is located ∼ 6 arcsec apart from the position of XRISM J0602-4006.
The flare started at 2026-05-08 at ∼ 17:18 TT. The flare reached its peak on 2026-05-08 at ∼ 19:06. The flare exponentially decayed in ∼ 104 sec.
The peak flux is calculated as 5 × 10-13 erg s-1 cm-2 (0.4 – 10.0 keV). A systematic error of roughly 20% should be taken into account. The corresponding luminosity is 1 × 1032 erg s-1 by assuming the distance to XRISM J0602-4006 of 1.3 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 and their corresponding counterparts in the same field of view.
