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arXiv · astro-ph/0209098

XMM-NEWTON Observation of the Seyfert 2 Galaxy NGC 4138

L. Foschini·F. Panessa·A. L. Longinotti·L. C. Ho·L. Bassani·M. Cappi·M. Dadina·G. Malaguti·G. Di Cocco·F. Gianotti·J. B. Stephen·M. Trifoglio
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Abstract

The XMM-Newton data presented here are the first X-ray observation of the Seyfert 2 galaxy NGC4138. Although the galaxy has been pointed by ROSAT-HRI, it was not detected, with a flux upper limit of about 1.1x10^-13 erg cm^-2 s^-1 in the 0.2-2.4 keV energy band. XMM-Newton performed the observation on 26 November 2001. The source is detected for the first time in X-rays with F[0.2-2.4]=1.0x10^-13 erg cm^-2 s^-1, in agreement with the upper limit of ROSAT. The source spectrum is typical of Seyfert 2 galaxies. We find heavy obscuration (N_H about 8x10^22 cm^-2) and a flat photon index (1.6). The source intrinsic luminosity is about 5x10^41 erg/s in the 0.5-10 keV energy band.

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L. Foschini, F. Panessa, A. L. Longinotti, L. C. Ho, L. Bassani, M. Cappi, M. Dadina, G. Malaguti, G. Di Cocco, F. Gianotti, J. B. Stephen, M. Trifoglio. 2002-09-05. XMM-NEWTON Observation of the Seyfert 2 Galaxy NGC 4138. https://arxiv.org/abs/astro-ph/0209098

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