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Relationship between X-ray and ultraviolet emission in 3C 273

S. Paltani·T. J. -L. Courvoisier·M. Turler·R. Walter
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Abstract

In 3C 273, ultraviolet flux and X-ray flux measured by BATSE are not well correlated, contrarily to predictions of several models, unless the X-ray flux lags the UV emission by 1.75 yr. The absence of observed correlation at small lag cannot be due to spectral variability. A Comptonizing corona model is however compatible with all UV and X-ray observations covering the BATSE period.

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S. Paltani, T. J. -L. Courvoisier, M. Turler, R. Walter. 1997-12-17. Relationship between X-ray and ultraviolet emission in 3C 273. https://doi.org/10.1016/s0920-5632(98)00259-x

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