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Published online by Cambridge University Press: 30 March 2016
After the first year of performance of SIGMA, more than 390 hours of data on the Galactic Centre region have been recorded. This survey establishes the extremely variable nature of this region. During a period of 6 months, 3 sources have dominated successively: 1E 1740.7-2942, GRS 1758-258, GX1 + 4. Concerning the two first sources, their spectral shape and their variability suggest to include them in the list of the black hole candidates.