This Letter presents the first results of an observational campaign to study the Galactic center with INTEGRAL, the Internaltional Gamma-Ray Astrophysics Laboratory. Mosaicked images were constructed using data obtained with ISGRI, the soft gamma-ray instrument of the coded aperture IBIS imager, in the energy ranges 20–40 and 40–100 keV. These give a yet unseen view of the high-energy sources of this region in hard X-rays and gammarays with an angular resolution of 12 ′ (FWHM). We report on the discovery of a source, IGR J1745.6–2901, coincident with the Galactic nucleus Sgr A ∗ to within 0 ′.9. Located at R.A.(J2000.0) = 17 h 45 m 38 s.5, decl.(J2000.0) =−29 ◦ 01 ′ 15 ′ ′ , the source is visible up to about 100 keV with a 20–100 keV luminosity at 8 kpc of (2.89±0.41)× 10 35 ergs s −1. Although the new INTEGRAL source cannot unequivocally be associated to the Galactic nucleus, this is the first report of significant hard X-ray emission from within the inner 10 ′ of the Galaxy and a contribution from the Galactic supermassive black hole itself cannot be excluded
To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.