Integral

Integral [ESA]

Integral (International Gamma Ray Astrophysics Laboratory) was selected by the ESA Science Programme Committee on 3 June 1993 as the next ESA medium-size scientific mission (M2) of the Horizon 2000 programme to be launched in 2002. The mission is conceived as an observatory led by ESA with contributions from Russia (PROTON launcher) and NASA (Deep Space Network ground station).

The ESA scientific mission INTEGRAL (The International Gamma-Ray Astrophysics Laboratory is dedicated to the fine spectroscopy (E/deltaE = 500) and fine imaging (angular resolution: 12 arcmin FWHM) of celestial gamma-ray sources in the energy range 15 keV to 10 MeV with concurrent source monitoring in the X-ray (3-35 keV. and optical (V-band, 550 nm) energy ranges.

The mission utilises the service module (bus) under development for the ESA XMM project. Integral will be launched by a Russian Proton into a highly eccentric 72-hour orbit. The nominal lifetime of the observatory will be 2 years with possible extension to up to 5 years. Most of the observing time will be made available to the worldwide scientific community.

INTEGRAL will carry two main Gamma-ray instruments:

• SPI Spectrometer : spectral analysis of Gamma-ray point sources and diffuse line emission sources in 20 keV.- 8 MeV energy range. CESR (Toulouse) and MPI (Garching), plus others. E/deltaE=500
• Imager IBIS: continuum and broad-line emission imaging of all classes of object in the energy range 15 keV.- 10 MeV. IAS/Rome, CE-Saclay and ITESRE (Bologna), plus others. Angular resolution 12'

Two other instruments complement the Gamma-ray detectors:

• the OMC (optical monitoring camera) and
• the JEM-X X-ray monitor