SPI (Spectrometer for INTEGRAL) is a high spectral resolution gamma-ray telescope to be flown on board the ESA mission INTEGRAL. It consists of an array of 19 closely packed Germanium detectors surrounded by an active anticoincidence shield of EGO. The imaging capabilities of the instrument are obtained with a tungsten coded aperture mask located 1.7 m from the Ge array. The fully coded field-of-view is 16 degrees and the angular resolution approximate to 2 degrees. The energy range extends from 20 keV to 8 MeV with a typical energy resolution approximate to 2 keV at 1 MeV. The point-source narrow-line sensitivity is estimated to be (3-7) x 10(-6) ph/cm(-2) s(-1) over most of the energy range of the instrument (E > 200 keV) for a 10(6) s observing time. With these expected performances a major step forward can be expected in fine gamma-ray spectroscopy of astrophysical objects.
Vedrenne, G. ; Leleux, Pierre ; et. al. The SPI Spectrometer for the integral mission.Nordic Conference in Theoretical High Energy Astrophysics (COPENHAGEN(Denmark), Sep 14-16, 1997). In: Physica Scripta. Topical Issues, Vol. T77, p. 35-38 (1998)
