Letter to the Editor

INTEGRAL/SPI ground calibration

¹ DSM/DAPNIA/Service d'Astrophysique, CEA Saclay, 91191 Gif-sur-Yvette, France,
² Centre d'Études Spatiales des Rayonnements, 9 avenue du Colonel Roche, 31028 Toulouse, France
³ Max-Planck-Institut für extraterrestrische Physik, Giessenbachstraße, 85748 Garching, Germany
⁴ NASA/Goddard Space Flight Center, code 661, Greenbelt, MD 20771, USA
⁵ Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse, IN2P3-CNRS, 91405 Orsay Campus, France
⁶ CEA Bruyères-le-Châtel, BP 12, 91680 Bruyères-le-Châtel, France
⁷ CNES/Centre Spatial de Toulouse, 18 avenue E. Belin, 31401 Toulouse, France
⁸ Universitat de Valencia, IFIC, Dr Moliner 50, 46100 Burjassot, Valencia, Spain
⁹ Univ. of Louvain, chemin du Cyclotron, 1348 Louvain-La-Neuve, Belgium

Corresponding author: D. Attié, David.Attie@cea.fr

Received: 14 July 2003
Accepted: 26 August 2003

Abstract

Three calibration campaigns of the spectrometer SPI have been performed before launch in order to determine the instrument characteristics, such as the effective detection area, the spectral resolution and the angular resolution. Absolute determination of the effective area has been obtained from simulations and measurements. At 1 MeV, the effective area is 65 cm² for a point source on the optical axis, the spectral resolution ~2.3 keV. The angular resolution is better than 2.5° and the source separation capability about 1°. Some temperature dependant parameters will require permanent in-flight calibration.