Related papers: Acceleration and Parallax Effects in Gravitational…
(abridged) Some difficulties in determining the physical properties that lead to observed anomalies in microlensing light curves, such as the mass and separation of extra-solar planets orbiting the lens star, or the relative source-lens…
We report the result of the analysis of the light curve of the microlensing event MOA-2009-BLG-016. The light curve is characterized by a short-duration anomaly near the peak and an overall asymmetry. We find that the peak anomaly is due to…
Most transit microlensing events due to very low-mass lens objects suffer from extreme finite-source effects. While modeling their light curves, there is a known continuous degeneracy between their relevant lensing parameters, i.e., the…
Extended source effects can be seen in gravitational lensing events when sources cross critical lines. Those events probe the stellar intensity profile and could be used to measure limb darkening coefficients to test stellar model…
For microlenses with sufficiently low mass, the angular radius of the source star can be much larger than the angular Einstein ring radius of the lens. For such extreme finite source effect (EFSE) events, finite source effects dominate…
When there is more than one source of light along the line of sight to a gravitationally lensed object, the characteristics of the observed light curve are influenced by the presence of the light that is not lensed. In this paper we develop…
We present the first detection of parallax effects in a gravitational microlensing event. Parallax in a gravitational microlensing event observed only from the Earth appears as a distortion of the lightcurve due to the motion of the Earth…
The parallax effect in ground-based microlensing (ML) observations consists of a distortion to the standard ML light curve arising from the Earth's orbital motion. In most cases, the resolution in current ML surveys is not accurate enough…
In this paper, we investigate the color changes of gravitational microlensing events caused by the two different mechanisms of differential amplification for a limb-darkened extended source and blending. From this investigation, we find…
In this paper, we demonstrate the severity of the degeneracy between the microlens-parallax and lens-orbital effects by presenting the analysis of the gravitational binary-lens event OGLE-2015-BLG-0768. Despite the obvious deviation from…
A planetary microlensing signal is generally characterized by a short-term perturbation to the standard single lensing light curve. A subset of binary-source events can produce perturbations that mimic planetary signals, thereby introducing…
If gravitational microlensing occurs in a binary-source system, both source components are magnified, and the resulting light curve deviates from the standard one of a single source event. However, in most cases only one source component is…
A major problem in the interpretation of microlensing events is that the only measured quantity, the Einstein time scale t_E, is a degenerate combination of the three quantities one would like to know, the mass, distance, and speed of the…
In gravitational microlensing, binary systems may act as lenses or sources. Identifying lens binarity is generally easy especially in events characterized by caustic crossing since the resulting light curve exhibits strong deviations from…
Gravitational lensing is the phenomenon arising when light rays are deflected by the mass between the source and the observer. Largely magnified and highly distorted images of background galaxies are formed by these angular deflections if…
It is known that a relative translational motion between the deflector and the observer affects gravitational lensing. In this paper, a lens equation is obtained to describe such effects on actual lensing observables. Results can be easily…
In the process of analyzing an observed light curve, one often confronts various scenarios that can mimic the planetary signals causing difficulties in the accurate interpretation of the lens system. In this paper, we present the analysis…
We study microlensing light curves by a triple lens, in particular, by a primary star plus two planets. A four-fold degeneracy is confirmed in the light curves, similar to the close and wide degeneracy found in a double lens. Furthermore,…
The current modelling of single microlensing light curves neglects the possibility that only a fraction of the light is due to the lensed star, the remaining being due to a close, unresolved blend, which may be related or unrelated to the…
Gravitational microlensing constraints on non-standard compact objects are conventionally derived assuming lenses trace the dark matter halo with velocities following a Maxwell-Boltzmann distribution centered around $10^{-3}c$. However, a…