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Evidence for a source size of less than 2000 AU in Quasar 2237+0305

Atsunori Yonehara
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Abstract

Recently, OGLE team have reported clear quasar microlensing signal in Q2237+0305. We have analyzed the microlens event of ``image C'' by using their finely and densely sampled lightcurves. From lightcurve fitting, we can unambiguously set the source size of $\lsim 0.98$ Einstein Ring radius as a conservative limit. This limit corresponds to $2000 {\rm (AU)}$, if we adopt $M_{\rm lens} \sim 0.1M_{\odot}$ obtained by a recent statistical study of mean mass of lens object. This gives a clear evidence for the existence of an accretion disk in the central region of the quasar.

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Atsunori Yonehara. 2000-12-11. Evidence for a source size of less than 2000 AU in Quasar 2237+0305. https://doi.org/10.1086/319090

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