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arXiv · 0912.2145

Short-duration lensing events: II. Expectations and Protocols

Rosanne Di Stefano
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Abstract

Ongoing microlensing observations by OGLE and MOA regularly identify and conduct high-cadence sampling of lensing events with Einstein diameter crossing time, tau_E, of 16 or fewer days. Events with estimated values of tau_E of one to two days have been detected. Short duration events tend to be generated by low-mass lenses or by lenses with high transverse velocities. We compute the expected rates, demonstrate the expected ranges of parameters for lenses of different mass, and develop a protocol for observing and modeling short-duration events. Relatively minor additions to the procedures presently used will increase the rate of planet discovery, and also discover or place limits on the population of high-speed dim stars and stellar remnants in the vicinity of the Sun.

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Rosanne Di Stefano. 2009-12-11. Short-duration lensing events: II. Expectations and Protocols. https://doi.org/10.1088/0067-0049/201/2/21

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