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

Authors :: S. Paltani
M. Turler
R. Walter
T. J. L. Courvoisier
Publication Year :: 1997
Publisher :: arXiv, 1997.
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.<br />Comment: LaTeX, 4 pages, 6 figures. espcrc2.sty style file included. Poster contribution to the symposium "The Active X-ray Sky: Results from BepppoSAX and Rossi-XTE", Rome, October 1997