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arXiv · 1508.07018

Estimating Finite Source Effects in Microlensing Events due to Free-Floating Planets with the Euclid Survey

Lindita Hamolli·Mimoza Hafizi·Francesco De Paolis·Achille A. Nucita
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Abstract

In recent years free-loating planets (FFPs) have drawn a great interest among astrophysicists. Gravitational microlensing is a unique and exclusive method for their investigation which may allow obtaining precious information about their mass and spatial distribution. The planned Euclid space-based observatory will be able to detect a substantial number of microlensing events caused by FFPs towards the Galactic bulge. Making use of a synthetic population algorithm, we investigate the possibility of detecting finite source effects in simulated microlensing events due to FFPs. We find a significant efficiency for finite source effect detection that turns out to be between 20% and 40% for a FFP power law mass function index in the range [0.9, 1.6]. For many of such events it will also be possible to measure the angular Einstein radius and therefore constrain the lens physical parameters. These kinds of observations will also offer a unique possibility to investigate the photosphere and atmosphere of Galactic bulge stars.

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Lindita Hamolli, Mimoza Hafizi, Francesco De Paolis, Achille A. Nucita. 2015-08-27. Estimating Finite Source Effects in Microlensing Events due to Free-Floating Planets with the Euclid Survey. https://doi.org/10.1155/2015%2F402303

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