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Principal component analysis of the X-ray variability in NGC 7469

A. J. Blustin·S. V. Fuerst·G. Branduardi-Raymont·M. J. Page·E. Behar·J. S. Kaastra
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Abstract

We apply Principal Component Analysis (PCA) to study the variability of the X-ray continuum in the Seyfert 1 galaxy NGC 7469. The PCA technique is used to separate out linear components contributing to variability between multiple datasets; the technique is often used in analysis of optical spectra, but has rarely been applied to AGN X-ray spectroscopy. Running a PCA algorithm on 0.3-10 keV EPIC data from a 150 ks XMM-Newton observation of NGC 7469, we describe the spectral components extracted and evaluate the usefulness of the PCA technique for understanding the X-ray continuum in AGN.

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A. J. Blustin, S. V. Fuerst, G. Branduardi-Raymont, M. J. Page, E. Behar, J. S. Kaastra. 2005-10-26. Principal component analysis of the X-ray variability in NGC 7469. https://arxiv.org/abs/astro-ph/0510754

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