First Announcement of Opportunity


After the successful launch of XRISM on September 7, 2023 and the completion of the critical operation period, the first Announcement of Opportunity for the Guest Observer program opened on November 15, 2023.

In consideration of ESA’s contribution to XRISM, not less than 8% of the total Guest Observing Time, or an equivalent return as mutually agreed, shall be allocated to ESA. The ESA Director of Science has thus issued the invitation to submit Guest Observer proposals: Letter by ESA Director of Science. Contingent upon the successful completion of the IOC and PV phase activities, Cycle 1 will commence on or about August 1, 2024, and last for a period of approximately 12 months.

The instructions to submit proposals were summairsed in the Announcement of Opportunity for the XRISM GO program and the The XRISM Proposers’ Observatory Guide.

Further information about XRISM can be found in this XRISM Quick Reference guide.

Information for studies of feasibility can be found under XRISM Proposal Tools

Response files for Cycle 1 assuming the Resolve Gate Valve Closed

Documents and Resources describing the status of the mission and the performance of the science payload are available from the archive web page of the XRISM Science Performance Workshop

For any questions, the European community is encouraged to make use of the European XRISM User Support Portal.

Proposal Submission:

The proposal submission deadline has passed. 43 proposals were received. The European Observing programme is oversubscribed by a factor ~7 (in time). Results of the review will be communicated before the end of July.