Paper 13093-236
X-ray transient search using XRISM/Xtend
On demand | Presented live 19 June 2024
Abstract
The X-ray Imaging Spectroscopy Mission (XRISM) was launched on 2023-09-06 (UT). The onboard Xtend camera is now performing spectral imaging in the 0.4–13 keV band. Utilizing the wide field of view of Xtend of 38′ ×38′, we have been conducting searches for transient sources once a day, under the name of “XRISM/Xtend Transient Search (XTS)”. We report an Astronomer’s Telegram (ATel) within ∼1 day after downlinking the data from the satellite. Since the beginning of March 2024, when the XTS began full-scale operations, through early July, we issued nine ATel reports. The sensitivity limit of XTS is about 10−14 erg s−1cm−2 for a one-day observation, i.e. for an exposure time of ∼40 ks with the typical XRISM observing efficiency of about 50%. This sensitivity limit is orders of magnitude fainter than those obtained with all-sky survey missions such as MAXI and Einstein probe. It is comparable to those of Swift/XRT and eROSITA/SRG. XRISM observations are 4 days long on average, allowing for searches of sources that vary on time scales of more than one day, and down to the 10−14 erg s−1cm−2 flux range. Consequently, XRISM now plays a key role in time-domain astronomy.
Presenter
Yohko Tsuboi
Chuo Univ. (Japan)
Yohko Tsuboi received her BS, MS, and PhD degrees in science from the University of Kyoto in 1994, 1996, and 1999, respectively. She is a professor at Department of Physics, Faculty of Science and Engineering, Chuo University. She is a member of the Science Operations team of the X-Ray Imaging and Spectroscopy Mission (XRISM) project, and then established Transient Search Team.