20th Announcement of Opportunity (AO-20)


This Announcement solicits proposals for observations to be carried out in 2023. The letter from ESA's Director of Science, inviting you to participate in the 20th Call for Proposals, is available here.


Release of AO-20: Call for observing time proposals   2 March 2022
Deadline for submission of observing time proposals   1 April 2022 (14:00 CEST)
Meeting of the Time Allocation Committee (TAC)   23-25 May 2022
Start AO-20 cycle of observation   1 January 2023

Important Notes

Please take note of the following points:

  • ESA provides the opportunity to propose for coordinated observations with XMM-Newton, NASA's NuSTAR telescope and/or NASA's Neil Gehrels Swift Observatory with a total of 300 ks, 100 ks and 150 ks, respectively, of their available time. Note that through an agreement with ESA, the Fermi project of NASA offers the possibility to obtain observing time with INTEGRAL through a single proposal to NASA via the Fermi AO.

  • Following a recommendation by the IUG, the time for execution of TOO observations is set to 3 Ms. This is allocated for long-term planning before the start of the AO. More time may be allocated to TOO observations during the execution of the AO if justified on the basis of scientific merit. Note that if a TOO is warranted, which is not approved for the current ongoing AO, an out-of-TAC (or unsolicited) TOO may be requested. Examples are new events or unexpected behaviour in known sources. Requests are to be submitted via the INTEGRAL TOO Notification web page.

  • The INTEGRAL Project has signed a Memorandum of Understanding (MoU) with the IceCube Collaboration, and Letters of Intent (LoIs) with the deep-sea neutrino telescope ANTARES and the SUPERB Project to participate in follow-up campaigns of ultra high energy neutrino events, and fast radio bursts. It is important to note that it is not possible to propose for time bound by these MoUs/LoIs.

  • This AO it is not possible to submit new Key Programme proposals with observations spanning two AO cycles (so-called multi-year proposal). Confirmation of on-going multi-year proposals are still allowed.

  • The rectangular dithering on a 5x5 grid is the standard observation pattern. In a few cases a hexagonal pattern is allowed. Observations with custom patterns are strongly discouraged. They will be considered only for A-grade proposals, and their scheduling will be on best-effort basis.

  • Data or science rights to the targets or science in the field of view (FOV) of the instruments will be allocated to PIs of accepted proposals with a 1-year proprietary period. If the PI is from a country other than the Russian Federation, the rest of the field will be made public immediately. Proposals where the PI is from the Russian Federation follow a similar kind of policy, except that the rest of the field will be made public only through the consolidated data programme. The Russian Federation scientists currently working at Russian Federation scientific institutes still have exceptional access to the near-real time data of the rest of the field.

  • Due to star-tracker viewing constraints, INTEGRAL cannot point to the Earth and/or other Solar system objects (including our Moon). There is, however, a way to circumvent this: let the object pass through the field-of-view of the instruments. Such observations have been done in the past, but they require special operations. Anyone interested in studying Solar system objects, is encouraged to contact us via the INTEGRAL Helpdesk.

We encourage you to use this LaTeX template, and refer to this checklist.




Staying informed