A Rapid Microlensing Event in the Q0957+561 A,B Gravitational Lens System
نویسنده
چکیده
We re-analyze brightness data sampled intensively over 5 nights at two epochs separated by the quasar lens time delay, to examine the nature of the observed microlensing. We find strong evidence for a microlensing event with an amplitude of 1% and a time scale of twelve hours. The existence of such rapid microlensing, albeit at low amplitude, imposes constraints on the nature of the quasar and of the baryonic dark matter. Subject headings: quasars: individual (0957+561) — gravitational lensing — galaxies: halos
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تاریخ انتشار 2008