SIMBAD references

The ESA observatory INTEGRAL (International Gamma-Ray Astrophysics Laboratory) is dedicated to the fine spectroscopy (2.5keV FWHM @ 1MeV) and fine imaging (angular resolution: 12arcmin FWHM) of celestial gamma-ray sources in the energy range 15keV to 10MeV with concurrent source monitoring in the X-ray (3-35keV) and optical (V-band, 550nm) energy ranges. INTEGRAL carries two main gamma-ray instruments, the spectrometer SPI (Vedrenne et al., 2003A&A...411L..63V) - optimized for the high-resolution gamma-ray line spectroscopy (20 keV-8 MeV), and the imager IBIS (Ubertini et al., 2003A&A...411L.131U) - optimized for high-angular resolution imaging (15keV-10MeV). Two monitors, JEM-X (Lund et al., 2003A&A...411L.231L) in the (3-35)keV X-ray band, and OMC (Mas-Hesse et al., 2003A&A...411L.261M) in optical Johnson V-band complement the payload. The ground segment includes the Mission Operations Centre at ESOC, ESA and NASA ground stations, the Science Operations Centre at ESTEC and the Science Data Centre near Geneva. INTEGRAL was launched on 17 October 2002. The observing programme is well underway and sky exposure (until June 2003) reaches ∼1800ks in the Galactic plane. The prospects are excellent for the scientific community to observe the high energy sky using state-of-the-art gamma-ray imaging and spectroscopy. This paper presents a high-level overview of INTEGRAL.