Extending the Planetary Mass Function to Earth Mass by Microlensing at Moderately High Magnification

Fumio Abe; Charlotte Airey; Ellen Barnard; Julie Baudrey; Christine Botzler; Dimitri Douchin; Matthew Freeman; Patricia Larsen; Anna Niemiec; Yvette Perrott; Lydia Philpott; Nicholas Rattenbury; Philip Yock

doi:10.1093/mnras/stt318

arXiv · 1303.4123

Extending the Planetary Mass Function to Earth Mass by Microlensing at Moderately High Magnification

Fumio Abe·Charlotte Airey·Ellen Barnard·Julie Baudrey·Christine Botzler·Dimitri Douchin·Matthew Freeman·Patricia Larsen·Anna Niemiec·Yvette Perrott·Lydia Philpott·Nicholas Rattenbury·Philip Yock

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Abstract

A measurement by microlensing of the planetary mass function of planets with masses ranging from 5M_E to 10M_J and orbital radii from 0.5 to 10 AU was reported recently. A strategy for extending the mass range down to (1-3)M_E is proposed here. This entails monitoring the peaks of a few tens of microlensing events with moderately high magnifications with 1-2m class telescopes. Planets of a few Earth masses are found to produce deviations of ~ 5% to the peaks of microlensing light curves with durations ~ (0.7-3)hr in events with magnification ~ 100 if the projected separation of the planet lies in the annular region (0.85-1.2)r_E. Similar deviations are produced by Earth mass planets in the annular region (0.95-1.05)r_E. It is possible that sub-Earths could be detected very close to the Einstein ring if they are sufficiently abundant, and also planetary systems with more than one low mass planet.

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Fumio Abe, Charlotte Airey, Ellen Barnard, Julie Baudrey, Christine Botzler, Dimitri Douchin, Matthew Freeman, Patricia Larsen, Anna Niemiec, Yvette Perrott, Lydia Philpott, Nicholas Rattenbury, Philip Yock. 2013-03-17. Extending the Planetary Mass Function to Earth Mass by Microlensing at Moderately High Magnification. https://doi.org/10.1093/mnras/stt318

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