A Possible Planetary Event OGLE-2002-BLG-055

TL;DR

This paper discusses a microlensing event with a single deviant data point suggesting a possible planetary companion, proposes observational strategy improvements, and highlights the challenge of model uniqueness with limited data.

Contribution

It introduces a modified observing strategy for microlensing events to better confirm planetary signals from sparse data points.

Findings

Single deviant point suggests a Jupiter-mass companion.

Current data insufficient for unique model fitting.

Proposed strategy aims to improve future event analysis.

Abstract

The microlensing event OGLE-2002-BLG-055 has a single, but very reliable data point, deviating upward from a single source microlensing light curve by 0.6 mag. The simplest interpretation calls for a binary lens with a strong parallax effect and the mass ratio in the range 0.01 - 0.001, putting the companion in the Jupiter mass range. Given only a single deviant point it is impossible to fit a unique model. We propose a modification of OGLE observing strategy: instant verification of a reality of future deviant points, followed by a frequent time sampling, to make a unique model fit possible.