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The XMM-Newton View of the Nucleus of NGC 4261

R. M. Sambruna·M. Gliozzi·M. Eracleous·W. N. Brandt·R. Mushotzky
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Abstract

We present the first results from an XMM-Newton observation of the FRI galaxy NGC 4261, which harbors a supermassive black hole and a low-ionization nuclear emission-line region (LINER). Here we focus on the X-ray properties of the nucleus, using the EPIC pn data. The 0.6-10 keV continuum in best fitted by a thermal component with kT ~0.7 keV, plus a power law with photon index ~1.4, absorbed by a column density NH~4e22 cm-2. An unresolved Fe K emission line with EW 280 eV is detected at 7 keV. We also detect, for the first time, short-term flux variability from the nucleus, on a timescale of 3-5 ks. The short-term variations rule out an ADAF as the only production mechanism of the X-ray continuum. Instead, we argue that the inner jet contributes to the emission in the X-ray band.

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R. M. Sambruna, M. Gliozzi, M. Eracleous, W. N. Brandt, R. Mushotzky. 2003-02-05. The XMM-Newton View of the Nucleus of NGC 4261. https://doi.org/10.1086/374612

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