Speaker
Description
X-ray Imaging and Spectroscopy Mission (XRISM) has two X-ray instruments. Resolve, an X-ray microcalorimeter, has an extreme energy resolution of 5 eV at 6 keV. Xtend, an X-ray CCD array, has a large field of view (FoV) of 38 arcmin square, which gives us opportunities to observe many serendipitous sources. We developed the XRISM/Xtend Transient Search (XTS), a project to quick search and fast report for X-ray transient detected by Xtend. XTS has ~ 3 orders of magnitude higher sensitivity than that of MAXI (with limited FoV). XTS is the first attempt to make the fast reports for transient sources with a pointing satellite (i.e., non-survey type mission). XTS started on Mar. 2024. We have reported 17 transients via the Astronomer's Telegram (ATel) so far (2024-09-30). Most of them are stellar flares with X-ray fluxes of 10^-13 -- 10^-11 erg/s/cm^2. In this presentation, we report the development, operation and results during the "performance verification phase" of XRISM by Sep. 2024.