XMM-Newton observation of the brightest X-ray flare detected so far from Sgr A* D. Porquet, P. Predehl, B. Aschenbach, N. Grosso, A. Goldwurm, P. Goldoni, R. S. Warwick and A. Decourchelle A&A, 407 1 (2003) L17-L20 Published online: 17 November 2003 DOI: 10.1051/0004-6361:20030983