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Optical and X-ray monitoring of the NLS1 galaxy Ark 564

I. E. Papadakis·W. Brinkmann·H. Negoro·E. Detsis·I. Papamastorakis·M. Gliozzi
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Abstract

The Narrow-line Seyfert galaxy Ark 564 was monitored between June 04, 2000 and June 24, 2000 from Skinakas Observatory. The B,V,R and I band light curves show night to night variations of 0.1 mag. Comparison with X-ray data from a simultaneous ASCA observation shows that the X-ray variations are more pronounced than in the optical band. Cross correlation analysis yields a time lag of ~ 0.8 days in the sense that the X-rays are leading the optical but with low statistical significance. We discuss possible implications of our results to current physical models of AGN.

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I. E. Papadakis, W. Brinkmann, H. Negoro, E. Detsis, I. Papamastorakis, M. Gliozzi. 2000-12-14. Optical and X-ray monitoring of the NLS1 galaxy Ark 564. https://arxiv.org/abs/astro-ph/0012317

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