4 papers
Identification of Bright Lenses from the Astrometric Observations of Gravitational Microlensing Events
Cheongho Han, Youngjin Jeong
When a source star is gravitationally microlensed by a dark lens, the centroid of the source star image is displaced relative to the position of the unlensed source star with an el…
The Effect of Bright Lenses in the Astrometric Measurements of MACHO Proper Motion
Youngjin Jeong, Cheongho Han, Sung-Hong Park
In current microlensing experiments, the information about the physical parameters of individual lenses are obtained from the Einstein timescales. However, the nature of MACHOs is…
Where Are the Binary Source Gravitational Microlensing Events? II
Cheongho Han, Youngjin Jeong
Currently, 6 candidate binary lens events have been reported, while only a single candidate binary source event has been reported. To account for the rarity of binary source events…
Observational Evidence for the Effect of Amplification Bias in Gravitational Microlensing Experiments
Cheongho Han, Youngjin Jeong
Recently Alard\markcite{alard1996} proposed to detect the shift of a star's image centroid, , as a method to identify the lensed source among blended stars. Goldberg & Woźniak\…