Evidence of a sub-solar star in a microlensing event toward the LMC

Abstract

Gravitational microlensing is known to be an impressive tool for searching dark, small, and compact objects that are missed by the usual astronomical observations. In this paper, by analysing multiple images acquired by DECam, we present the detection and a complete description of the microlensing event LMC J05074558-65574990 which is most likely due to a sub-solar object with mass (0.16±0.10) M⊙, hence in the mass range between a massive brown dwarf and a red dwarf, whose distance is estimated to be 7.8−3.4+4.1×102 pc thanks to the Gaia observation of the source, leading us to consider this lens as one the closest ever detected.