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Early Estimation of Microlensing Event Magnifications

Michael D. Albrow
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Abstract

Gravitational microlensing events with high peak magnifications provide a much enhanced sensitivity to the detection of planets around the lens star. However, estimates of peak magnification during the early stages of an event by means of chi^2 minimization frequently involve an overprediction, making observing campaigns with strategies that rely on these predictions inefficient. I show that a rudimentary Bayesian formulation, incorporating the known statistical characteristics of a detection system, produces much more accurate predictions of peak magnification than chi^2 minimisation. Implementation of this system will allow efficient follow-up observing programs that focus solely on events that contribute to planetary abundance statistics.

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Michael D. Albrow. 2004-02-13. Early Estimation of Microlensing Event Magnifications. https://doi.org/10.1086/383565

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