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XMM - Newton observations of Markarian 421

W. Brinkmann·S. Sembay·R. G. Griffiths·G. Branduardi-Raymont·M. Gliozzi·Th. Boller·A. Tiengo·S. Molendi·S. Zane
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Abstract

The BL Lac object Mrk 421 was observed on May 25, 2000 during the XMM - Newton CAL/PV phase. The high throughput of the X-ray telescopes and the spectral capabilities of the instruments allow an uninterrupted temporal and spectral study of the source with unprecedented time resolution. Mrk 421 was found at a relatively high state with a 2-6 keV flux of (1.3 - 1.9)E-10 erg cm**-2 s **-1. The observed intensity variations by more than a factor of three at highest X-ray energies are accompanied by complex spectral variations with only a small time lag (tau = 265 {+116} {-102} seconds) between the hard and soft photons. The (0.2-10) keV spectrum can be well fitted by a broken power law and no absorption structures are found in the source spectrum at the high spectral resolution of the transmission gratings.

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W. Brinkmann, S. Sembay, R. G. Griffiths, G. Branduardi-Raymont, M. Gliozzi, Th. Boller, A. Tiengo, S. Molendi, S. Zane. 2000-11-09. XMM - Newton observations of Markarian 421. https://doi.org/10.1051/0004-6361%3A20000084

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