ToO Requests

ToO request form

NOTE: From September 1 to October 31, 2025, ToO observations based on requests will not be conducted due to planned gate valve opening operations, their preparatory work, and associated calibration observations.

Targets of the generic ToO program are expected to be "historic events that should not be overlooked".
The other ones, i.e., "Events expected to occur once or more every few years", may be regarded as a possible reserved ToO observation proposal for following Cycles of the guest observation program.
Refer to the list of approved generic ToO.

During XRISM operations, celestial targets are observable only when their solar angle is between 60 and 120 degrees. Meeting this criterion for the requested observation timing is required when submitting a ToO proposal. Please verify the visibility of your proposed targets using the online tool.

Click to Email -- for pre-approved ToO (targets approved as a Guest Observation cycle-1 target.)
Click to Email -- for generic ToO (not approved as GO target. The data will be open to the public.)

You can request of a pre-approved ToO or a generic ToO observation sending an e-mail to the XRISM operational team.
If the mailer does not open after clicking on "Click to Email", please send an e-mail to "xrism-too-trigger@ml.isas.jaxa.jp" with the following information.

• Subject
• for generic ToO - Generic ToO Request ***
• for pre-approved ToO - Pre-approved ToO Request ***


• Body
• PI's Information
• Your Name (e.g. Tashiro, Makoto):
• Institute (e.g. Saitama U.):
• Contact Email:


• Target information
• Target Name:
• RA:
• Dec:
• Object type (e.g. HMXB, BHB, GRB):
• Expected Resolve count rate:
• Maximum expected Resolve count rate:
• Approximate expected spectrum (e.g. Power Law with gamma 2.1):


• Justification (Any attachment file size must be below 5MB in total.)
• ToO type (generic ToO | pre-approved ToO):
• for generic ToO - Science justification (400 words max.):
• for pre-approved ToO - Trigger justification (400 words max.):
• Relevant URL (*optional):
• Likelihood (e.g. 73% within 3 days):


• Operational requirements
• Response time requested: within **+day/week
• the sooner the better? (yes | no):
• Response time justification:
• Observing time: ** ks
• for generic ToO - Justification for observing time:
• Observation mode
• Resolve (OPEN | ND filter):
• Xtend (FULL | 1/8 | 1/8+Burst):


• Others (*optional)
• Coordination with other observatories:
• Remarks: