Detection of hard X-ray emission from the Galactic nuclear region with INTEGRAL

G. Belanger; A. Goldwurm; P. Goldoni; J. Paul; R. Terrier; M. Falanga; P. Ubertini; A. Bazzano; M. Del Santo; C. Winkler; A. N. Parmar; E. Kuulkers; K. Ebisawa; J. P. Roques; N. Lund; F. Melia

doi:10.1086/381738

arXiv · astro-ph/0311147

Detection of hard X-ray emission from the Galactic nuclear region with INTEGRAL

G. Belanger·A. Goldwurm·P. Goldoni·J. Paul·R. Terrier·M. Falanga·P. Ubertini·A. Bazzano·M. Del Santo·C. Winkler·A. N. Parmar·E. Kuulkers·K. Ebisawa·J. P. Roques·N. Lund·F. Melia

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Abstract

This letter presents the first results of an observational campaign to study the Galactic Centre with INTEGRAL. The mosaicked images obtained with the IBIS/ISGRI coded aperture instrument in the energy ranges 20-40 and 40-100 keV, give a yet unseen view of the high-energy sources of this region in hard X- and gamma-rays with an angular resolution of 12 arcmin (FWHM). We report on the discovery of a source, IGR J17456-2901, coincident with the Galactic Nucleus SgrA* to within 0.9 arcmin. Located at R.A.(J2000.0) = 17h45m38.5s, Dec.(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) x 10^35 ergs/s. 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 arcmin of the Galaxy and a contribution from the galactic supermassive black hole itself cannot be excluded.

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G. Belanger, A. Goldwurm, P. Goldoni, J. Paul, R. Terrier, M. Falanga, P. Ubertini, A. Bazzano, M. Del Santo, C. Winkler, A. N. Parmar, E. Kuulkers, K. Ebisawa, J. P. Roques, N. Lund, F. Melia. 2004-06-22. Detection of hard X-ray emission from the Galactic nuclear region with INTEGRAL. https://doi.org/10.1086/381738

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