With the aim of taking full advantage of the complementarity of ESA's high energy observing facilities, both projects have agreed to establish an environment for those scientific programmes that require observations with both the XMM-Newton X-ray observatory and the INTEGRAL satellite to achieve outstanding and competitive results.
The issue of the XMM-Newton announcements of opportunity are separated by half a year from the INTEGRAL announcements such that coordinated programmes can easily be proposed on the basis of observations accepted by one of the two projects. By agreement with the XMM-Newton observatory, the INTEGRAL Time Allocation Committee may award up to 300 ks of XMM-Newton observing time for observations which are difficult to accommodate within the scheme described above:
Proposers wishing to make use of this opportunity will have to submit a single proposal in response to the INTEGRAL announcement of opportunity. Although time is requested on both observatories, it will be unnecessary to submit proposals to two separate review boards. A proposal submitted to INTEGRAL will be reviewed exclusively by the INTEGRAL observing time allocation committee.
The primary criterion for the award of observing time is that both INTEGRAL and XMM-Newton data are required to meet the scientific objectives of the proposal. The allocated XMM-Newton observing time should not exceed the allocated Integral observing time. Neither target of opportunity nor any other type of observations with a reaction time of less than 8 weeks from an unknown triggering date will be considered for this cooperative programme. Repeated observations are excluded from this joint programme.
It is the proposers' responsibility to provide a full and comprehensive scientific and technical justification for the requested observing time on both facilities. Both projects, the XMM-Newton and the INTEGRAL observatories, will perform feasibility checks of the proposals. They each reserve the right to reject any observation determined to be unfeasible for any reason.
Apart from the above, for both, the XMM-Newton and the INTEGRAL observatory, the general policies and procedures currently in force for the final selection of the proposals, the allocation of observing time, the execution of the observations, and the data rights remain unchanged.