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arXiv · 0809.2157

Q2237+0305 in X-rays: spectra and variability with XMM-Newton

E. V. Fedorova·V. I. Zhdanov·C. Vignali·G. G. C. Palumbo
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Abstract

X-ray observations of gravitationally lensed quasars may allow us to probe the inner structure of the central engine of a quasar. Observations of Q2237+0305 (Einstein Cross) in X-rays may be used to constrain the inner structure of the X-ray emitting source. Here we analyze the XMM-Newton observation of the quasar in the gravitational lens system Q2237+0305 taken during 2002. Combined spectra of the four images of the quasar in this system were extracted and modelled with a power-law model. Statistical analysis was used to test the variability of the total flux. The total X-ray flux from all the images of this quadruple gravitational lens system is 6 x 10^{-13} erg/cm2/s in the range 0.2-10 keV, showing no significant X-ray spectral variability during almost 42 ks of the observation time. Fitting of the cleaned source spectrum yields a photon power-law index of Gamma=1.82+0.07/-0.08. The X-ray lightcurves obtained after background subtraction are compatible with the hypothesis of a stationary flux from the source.

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E. V. Fedorova, V. I. Zhdanov, C. Vignali, G. G. C. Palumbo. 2008-09-12. Q2237+0305 in X-rays: spectra and variability with XMM-Newton. https://doi.org/10.1051/0004-6361:20078730

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