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arXiv · astro-ph/9801130

BeppoSAX detection of the Fe K line in the starburst galaxy NGC253

S. Mariani·M. Cappi·M. Persic·L. Bassani·G. G. C. Palumbo·L. Danese·A. J. Dean·G. Di Cocco·A. Franceschini·L. K. Hunt·F. Matteucci·E. Palazzi·Y. Rephaeli·P. Salucci·A. Spizzichino
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Abstract

Preliminary results obtained from BeppoSAX observation of the starburst galaxy NGC253 are presented. X-ray emission from the object is clearly extended but most of the emission is concentrated on the optical nucleus. Preliminary analysis of the LECS and MECS data obtained using the central 4' region indicates that the continuum is well fitted by two thermal components at 0.9 keV and 7 keV. Fe K line at 6.7 keV is detected for the first time in this galaxy; the line has an equivalent width of ~300eV. The line energy and the shape of the 2-10 keV continuum strongly support thermal origin of the hard X-ray emission of NGC253. From the measurement of the Fe K line the abundances can be unambiguously constrained to ~0.25 the solar value. Other lines clearly detected are Si, S and Fe XVIII/Ne, in agreement with ASCA results.

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S. Mariani, M. Cappi, M. Persic, L. Bassani, G. G. C. Palumbo, L. Danese, A. J. Dean, G. Di Cocco, A. Franceschini, L. K. Hunt, F. Matteucci, E. Palazzi, Y. Rephaeli, P. Salucci, A. Spizzichino. 1998-01-14. BeppoSAX detection of the Fe K line in the starburst galaxy NGC253. https://doi.org/10.1016/s0920-5632(98)00284-9

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