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Unveiling the nature of three INTEGRAL sources through optical spectroscopy

N. Masetti·E. Palazzi·L. Bassani·A. Malizia·J. B. Stephen
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Abstract

The results of an optical spectroscopy campaign performed at the Astronomical Observatory of Bologna in Loiano (Italy) on three hard X-ray sources detected by INTEGRAL (IGR J17303-0601, IGR J18027-1455 and IGR J21247+5058) are presented. These data have allowed a determination of the nature for two of them, with IGR J17303-0601 being a low mass X-ray binary in the Galaxy and IGR J18027-1455 a background Type 1 Seyfert galaxy at redshift z = 0.035. IGR J21247+5058, instead, has a quite puzzling spectroscopic appearance, with a broad, redshifted H_alpha complex superimposed onto a `normal' F/G-type Galactic star continuum: these features, together with the spatially coincident extended radio emission, might suggest a chance alignment between a relatively nearby star and a background radio galaxy. These results underline the still non-negligible importance of smaller telescopes in modern astrophysics.

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N. Masetti, E. Palazzi, L. Bassani, A. Malizia, J. B. Stephen. 2004-09-10. Unveiling the nature of three INTEGRAL sources through optical spectroscopy. https://doi.org/10.1051/0004-6361%3A200400078

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