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Reconstruction of the microlensing light curves of the Einstein Cross, QSO2237+0305: possible evidence of an accretion disk with a central hole

Dong-Wook Lee·J. Surdej·O. Moreau·C. Libbrecht·J. -F. Claeskens
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Abstract

Recent OGLE (Optical Gravitational Lensing Experiment) and GLITP (Gravitational Lens International Time Project) monitoring data for QSO 2237+0305 (Huchra et al.) have been analyzed through a newly optimized N-body microlensing analysis method, the Local HAE Caustic Modeling (LOHCAM). This method simultaneously solves for the size of the source and N-body HAE (High Amplification Events) caustic shapes in the source plane and determines those sizes only as a function of the projected transverse velocity of the source. By applying this method to the light curves of the A & C lensed components in the Einstein Cross, these data are accurately reconstructed for the first time. From these modeling studies, we report several interesting results: the minimum number of microlenses required for possible caustic models, the possible evidence of an accretion disk with a central hole at the heart of the quasar, the size of the UV-continuum source, the masses of the microlenses being directly responsible for the observed HAEs, the estimated mass range of a super massive black hole (SMBH) in QSO 2237+0305 and finally some clues for the direction of the source motion in the sky.

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Dong-Wook Lee, J. Surdej, O. Moreau, C. Libbrecht, J. -F. Claeskens. 2005-03-15. Reconstruction of the microlensing light curves of the Einstein Cross, QSO2237+0305: possible evidence of an accretion disk with a central hole. https://arxiv.org/abs/astro-ph/0503018

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