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Kinematics of LMC stellar populations and self-lensing optical depth

P. Salati·R. Taillet·E. Aubourg·N. Palanque-Delabrouille·M. Spiro
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Abstract

Recent observations give some clues that the lenses discovered by the microlensing experiments in the direction of the Magellanic Clouds may be located in these satellite galaxies. We re-examine the possibility that self-lensing alone may account for the optical depth measured towards the Large Magellanic Cloud (LMC). We present a self-consistent multi-component model of the LMC consisting of distinct stellar populations, each associated to a vertical velocity dispersion ranging from 10 to 60 km/s. The present work focuses on showing that such dispersions comply with current 20 - 30 km/s limits set by observation on specific LMC populations. We also show that this model reproduces both the 1-2 10^-7 observed optical depth and the event duration distribution.

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P. Salati, R. Taillet, E. Aubourg, N. Palanque-Delabrouille, M. Spiro. 1999-09-27. Kinematics of LMC stellar populations and self-lensing optical depth. https://arxiv.org/abs/astro-ph/9904400

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