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arXiv · 0905.2651

The accretion disc in the quasar SDSS J0924+0219

D. J. E. Floyd·N. F. Bate·R. L. Webster
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Abstract

We present single-epoch multi-wavelength optical-NIR observations of the "anomalous" lensed quasar SDSS J0924+0219, made using the Magellan 6.5-metre Baade telescope at Las Campanas Observatory, Chile. The data clearly resolve the anomalous bright image pair in the lensed system, and exhibit a strong decrease in the anomalous flux ratio with decreasing wavelength. This is interpreted as a result of microlensing of a source of decreasing size in the core of the lensed quasar. We model the radius of the continuum emission region, sigma, as a power-law in wavelength, sigma lambda^zeta. We place an upper limit on the Gaussian radius of the u'-band emission region of 3.04E16 h70^{-1/2} ( /M_sun)^{1/2} cm, and constrain the size-wavelength power-law index to zeta<1.34 at 95% confidence. These observations rule out an alpha-disc prescription for the accretion disc in SDSS J0924+0219 with 94% confidence.

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D. J. E. Floyd, N. F. Bate, R. L. Webster. 2009-05-16. The accretion disc in the quasar SDSS J0924+0219. https://doi.org/10.1111/j.1365-2966.2009.15045.x

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