Fast computation of quadrupole and hexadecapole approximations in microlensing with a single point-source evaluation

A. Cassan

doi:10.1093/mnras/stx849

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arXiv · 1703.03600

Fast computation of quadrupole and hexadecapole approximations in microlensing with a single point-source evaluation

A. Cassan

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Abstract

The exoplanet detection rate from gravitational microlensing has grown significantly in recent years thanks to a great enhancement of resources and improved observational strategy. Current observatories include ground-based wide-field and/or robotic world-wide networks of telescopes, as well as space-based observatories such as satellites Spitzer or Kepler/K2. This results in a large quantity of data to be processed and analyzed, which is a challenge for modeling codes because of the complexity of the parameter space to be explored, and the intensive computations required to evaluate the models. In this work, I present a method that allows to compute the quadrupole and hexadecapole approximation of the finite-source magnification with more efficiency that previously available codes, with routines about x6 and x4 faster respectively. The quadrupole takes just about twice the time of a point-source evaluation, which advocates for generalizing its use to large portion of the light curves. The corresponding routines are available as open-source python codes.

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A. Cassan. 2017-04-14. Fast computation of quadrupole and hexadecapole approximations in microlensing with a single point-source evaluation. https://doi.org/10.1093/mnras%2Fstx849

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