INTEGRAL - Extreme Universe Surveyor

The INTErnational Gamma Ray Astrophysics Laboratory, INTEGRAL, was an ESA mission with US and Russian participation with its primary instruments covering the hard X-ray/gamma-ray (keV – GeV) energy range within which fundamental changes from thermal to non-thermal astrophysical sources and phenomena are observable, the effects of light absorption are drastically reduced and a clearer picture of the Universe is possible. This is also the energy range where most of the extreme astrophysical behaviours take place, e.g. cosmic acceleration, explosions and accretion onto black holes and neutron stars; where variability is more the rule than the exception. A large field of view and the capability for long, uninterrupted observations enabled INTEGRAL to discover many new transients and unknown obscured sources. Further spectacular INTEGRAL results were obtained by measurements of isotopic radioactive decay lines and the electron-positron (e-e+) annihilation line. Also the secondary instruments sensitive in X-ray and optical light delivered important results.

Facts in a nutshell:


Illustration of the INTEGRAL instruments with essential properties, from top left to bottom right: the ‘Imager on Board the INTEGRAL Satellite’ (IBIS) with two layers: the ‘INTEGRAL Soft Gamma-Ray Imager’ (ISGRI) and the ‘Pixellated Imaging CsI Telescope’ (PICsIT), two identical ‘Joint European X-ray Monitors’ (JEM-X1 and JEM-X2), the ‘Optical Monitoring Camera’ (OMC), and the ‘SPectrometer aboard INTEGRAL’ (SPI).

In addition to the four prime instruments illustrated above, INTEGRAL operated the SPI Anticoincidence Shield (ACS) and the INTEGRAL Radiation Environment Monitor (IREM).

This suite of payload provided the following observational capabilities:

  • Wide-angle, time-resolved imaging, simultaneously in γ-ray, X-ray, and visual light,
  • Narrow-band, time-resolved wide-angle imaging in nuclear decay lines and the e-e+ annihilation line,
  • Broadband spectroscopy with medium resolution of high-energy sources, used, e.g., for measurements of magnetic field strengths in neutron stars via cyclotron lines,
  • γ-ray polarisation,
  • All-sky detection with precise timing of transient events,
  • Long uninterrupted observations separated by ∼10-hour duration perigee passages thanks to the highly elliptical 3-day (2.7-day after the modification to ensure re-entry) orbit around the Earth,
  • Particle radiation around Earth over total time span of 27 years until re-entry in February 2029; towards the end of the mission probing a large range of altitudes.​​​​​​​

New to INTEGRAL? Start here!

INTEGRAL Latest News

INTEGRAL Legacy User Validation & Feedback Exercise on June 22, 2026

17 April 2026 The final phases of development of the INTEGRAL Legacy Archive (ISLA) are well underway, and representatives of the scientific community will convene on June 22, 2026 10:30-12:00 CEST for an online presentation of the archive with an opportunity to advise on usability and user friendliness. The presentations may inspire ideas on how the external user community can help, e.g., contributions of community products that will be available via https://isla.esac.esa.int/isla/#/pages/community-products. Members of the public are welcome, anyone wishing to join the meeting, please send an email to the INTEGRAL Project Scientist. The main features on the user interface planned for ISLA have been implemented. They include 4 primary and 3 secondary portals:

  • Primary portals:
    • Data: searching for data to be downloaded or connected to ESA datalabs for analysis
    • Sources: high level products like time series, spectra and mosaics
    • All-Sky Maps: to view within the ESA Sky embedded widget exposure maps and other all-sky maps
    • Catalogs: to explore official catalogs available in the standard OSA format
  • Secondary portals:
    • GRB: to view within the ESA sky embedded widget the IBAS-detected GRBs and display their metadata
    • Community: where community members can provide links to their products
    • User Guides: where the documentation related to ISLA can be browsed.

What remains to be included by the end of 2026, i.e. the end of the post-operations phase, are additional products. Those currently planed for are:

  • OMC catalog and long term time series of detected high-energy sources
  • SPI published maps in all-sky viewer
  • SPI catalog and spectra of detected sources
  • JEM-X catalog of detected sources
  • Uncertain: Updated IBIS catalog of detected sources
  • Uncertain: Reprocessed IBIS products with final calibration

In addition, for the preservation of the ability to process consolidated INTEGRAL data using OSA, we plan to provide through ESA Datalabs (EDL) the OSA software together with a collection of Jupyter notebooks that provide templates and examples of how to run the core aspects of the analysis for IBIS and JEM-X, and possibly for SPI and OMC depending on time and support from collaborators.

Mark the date: INTEGRAL Legacy Conference

18 February 2026 The first INTEGRAL Legacy Conference will be organised by CEA and Paris-Saclay Universe Sciences Observatory on 19-23 October 2026 in “Institut Pascal” on the Paris-Saclay University Campus. Latest News can be found under https://integral2026.sciencesconf.org.

► Browse the INTEGRAL News Archive

Contact

INTEGRAL HelpDesk

INTEGRAL Project Scientist