16 February 2024
With the upcoming Cycle 1 proposal deadline on 4 April 2024, the X-ray Imaging and Spectroscopy Mission (XRISM) team announces the release of the Proposer’s Observatory Guide. This document is intended for researchers who have some general understanding of space-based astronomy and X-ray observations. It should provide the readers with a general understanding of the characteristics of the Resolve and Xtend instruments, including on-board data handling, calibration, and operational limitations. This document also explains the basics of how XRISM will be operated, and how observing time will be allocated. Based on this document, the reader should be able to determine whether XRISM is the appropriate instrument to address their scientific question, and how to design an appropriate observing program for the proposal.
Additionally, the XRISM Project announces the release of the first Early Release (ER) data, which observers can use to get familiar with XRISM observations, especially in the context of Cycle 1 Proposals. The data include X-ray spectra (in FITS format) obtained and reduced during the commissioning or calibration operations of the Resolve and Xtend instruments aboard XRISM. Note that the event files are not provided. Another important note is that these data were extracted assuming the current, still preliminary, calibration. While the calibration is advanced enough to demonstrate the data quality, reliable scientific results cannot be derived from these data products until full data and calibration are available. The Perseus cluster is the first dataset provided (for high-resolution events only). More ER data will be available in the future.