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arXiv · 1107.0982

A New Microlensing Event in the Doubly-Imaged Quasar Q0957+561

Laura J. Hainline·Christopher W. Morgan·J. N. Beach·C. S. Kochanek·Hugh C. Harris·T. Tilleman·Ross Fadely·Emilio E. Falco·T. X. Le
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Abstract

We present evidence for ultraviolet/optical microlensing in the gravitationally lensed quasar Q0957+561. We combine new measurements from our optical monitoring campaign at the United States Naval Observatory, Flagstaff (USNO) with measurements from the literature and find that the time-delay-corrected r-band flux ratio m_A - m_B has increased by ~0.1 magnitudes over a period of five years beginning in the fall of 2005. We apply our Monte Carlo microlensing analysis procedure to the composite light curves, obtaining a measurement of the optical accretion disk size, log {(r_s/cm)[cos(i)/0.5]^{1/2}} = 16.2^{+0.5}_{-0.6}, that is consistent with the quasar accretion disk size - black hole mass relation.

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Laura J. Hainline, Christopher W. Morgan, J. N. Beach, C. S. Kochanek, Hugh C. Harris, T. Tilleman, Ross Fadely, Emilio E. Falco, T. X. Le. 2011-07-05. A New Microlensing Event in the Doubly-Imaged Quasar Q0957+561. https://doi.org/10.1088/0004-637x/744/2/104

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