A BeppoSAX observation of 3C273: broadband spectrum and detection of a low-energy absorption feature

P. Grandi; M. Guainazzi; T. Mineo; A. N. Parmar; F. Fiore; A. Matteuzzi; F. Nicastro; G. C. Perola; L. Piro; M. Cappi; G. Cusumano; F. Frontera; S. Giarrusso; E. Palazzi; S. Piraino

arXiv · astro-ph/9707073

A BeppoSAX observation of 3C273: broadband spectrum and detection of a low-energy absorption feature

P. Grandi·M. Guainazzi·T. Mineo·A. N. Parmar·F. Fiore·A. Matteuzzi·F. Nicastro·G. C. Perola·L. Piro·M. Cappi·G. Cusumano·F. Frontera·S. Giarrusso·E. Palazzi·S. Piraino

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Abstract

We report the results of a 3C273 observation performed during the Science Verification Phase (SVP) of the BeppoSax satellite. The broad-band spectrum is well represented by a power-law between 1 keV and 200 keV. The spectral slope is flat (Γ~1.6) with a weak emission line at ~ 6.4 keV (rest frame) of EW ~ 30 eV. Below 1 keV, a deviation from a power-law due to an absorption feature plus a soft component is present. This is the first time that a feature in absorption at ~ 0.5 keV (observer frame) is unambiguously detected in 3C273.

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P. Grandi, M. Guainazzi, T. Mineo, A. N. Parmar, F. Fiore, A. Matteuzzi, F. Nicastro, G. C. Perola, L. Piro, M. Cappi, G. Cusumano, F. Frontera, S. Giarrusso, E. Palazzi, S. Piraino. 1997-07-07. A BeppoSAX observation of 3C273: broadband spectrum and detection of a low-energy absorption feature. https://arxiv.org/abs/astro-ph/9707073

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