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Under the current microlensing planet search strategy of monitoring events caused by stellar-mass lenses, only planets located within a narrow region of separations from central stars can be effectively detected. However, with the dramatic…

Astrophysics · Physics 2009-11-07 Cheongho Han , Young Woon Kang

We investigate the effect of a finite source on the planetary-lensing signals of high-magnification events. From this, we find that the dependency of the finite-source effect on the caustic shape is weak and perturbations survive even when…

Astrophysics · Physics 2011-02-11 Cheongho Han , Doeon Kim

Occultation and microlensing are different limits of the same phenomena of one body passing in front of another body. We derive a general exact analytic expression which describes both microlensing and occultation in the case of spherical…

Astrophysics · Physics 2009-11-07 Eric Agol

Due to their scarcity, microlensing events in the Galactic disk are of great interest and high-cadence photometric observations, supplemented by spectroscopic follow-up, are necessary for constraining the physical parameters of the lensing…

The Hubble Space Telescope (HST) and the Kepler space mission observed a large number of planetary transits showing anomalies due to starspot eclipses, with more such observations expected in the near future by the K2 mission and the…

Earth and Planetary Astrophysics · Physics 2014-07-18 Bence Béky , David M. Kipping , Matthew J. Holman

Currently, gravitational microlensing survey experiments toward the Galactic bulge field utilize two different methods of minimizing blending effect for the accurate determination of the optical depth \tau. One is measuring \tau based on…

Astrophysics · Physics 2009-11-13 Cheongho Han

We present the analysis of the microlensing event KMT-2018-BLG-1743. The light curve of the event, with a peak magnification $A_{\rm peak}\sim 800$, exhibits two anomaly features, one around the peak and the other on the falling side of the…

In this work, we present the analysis of the binary microlensing event OGLE-2018-BLG-0022 that is detected toward the Galactic bulge field. The dense and continuous coverage with the high-quality photometry data from ground-based…

Detecting compact objects by means of their gravitational lensing effect on an observed companion in a binary system has already been suggested almost four decades ago. However, these predictions were made even before the first observations…

Solar and Stellar Astrophysics · Physics 2015-05-19 S. Rahvar , A. Mehrabi , M. Dominik

We describe the feasibility of detecting the gravitational deflection of light emitted by stars moving under the influence of the massive object at the Galactic center. Light emitted by a star orbiting behind the central mass has a smaller…

Astrophysics · Physics 2009-11-10 Adi Nusser , Tom Broadhurst

We report the serendipitous detection of a very bright, very nearby microlensing event. In late October 2006, an otherwise unremarkable A0 star at a distance ~1 kpc (GSC 3656-1328) brightened achromatically by a factor of nearly 40 over the…

More than 100 microlensing events have been detected during the last ~4 years, most of them towards the Galactic Bulge. Since the line of sight towards the Bulge passes through the disk and the Bulge itself, the known stars towards the…

Astrophysics · Physics 2007-05-23 Kailash C. Sahu

We study light variability of gravitationally magnified high-redshift star clusters induced by a foreground population of microlenses. This arises as the incoherent superposition of light variations from a large number of source stars…

Astrophysics of Galaxies · Physics 2021-01-13 Liang Dai

Strongly lensed gravitational waves may pass through the stellar field of a lensing galaxy with additional modulations (on both phase and amplitude) due to gravitational microlensing effect of stars/remnants near the line of sight. These…

General Relativity and Quantum Cosmology · Physics 2025-10-21 Zhaoqi Su , Xikai Shan , Zhenwei Lyu , Junyao Zhang , Yebin Liu , Shude Mao , Huan Yang

Microlensing light curves are now being monitored with the precision required to detect small perturbations due to planetary companions of the primary lens. Microlensing is complementary to other planetary search techniques in its potential…

Astrophysics · Physics 2009-10-31 B. Scott Gaudi , Penny D. Sackett

Stellar microlensing is a powerful method to constrain compact dark matter models, uncover binary stars, and exoplanets during caustic crossing events. At cosmological distances, {\it James-Webb Space Telescope} ({\it JWST}) is routinely…

Astrophysics of Galaxies · Physics 2026-04-14 Sung Kei Li , Thomas Broadhurst , Jose M. Diego , Jeremy Lim , Jose M. Palencia , James Nianias

We describe the results of a search for microlensing events affecting stars in the outer bulge and inner disk of M31, due both to masses in M31 and the Galaxy. These observations, from 1994 and 1995 on the Vatican Advanced Technology…

Astrophysics · Physics 2009-10-28 Arlin P. S. Crotts , Austin B. Tomaney

If the Dark Matter consists of primordial black holes (PBHs), we show that gravitational lensing of stars being monitored by NASA's Kepler search for extra-solar planets can cause significant numbers of detectable microlensing events. A…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-30 Kim Griest , Matthew J. Lehner , Agnieszka M. Cieplak , Bhuvnesh Jain

A nearby star having a near-transit of a galaxy will cause a time-dependent weak lensing of the galaxy. Because the effect is small, we refer to this as weak microlensing. This could provide a useful method to weigh low-mass stars and brown…

Solar and Stellar Astrophysics · Physics 2015-05-14 Jonathan Coles , Prasenjit Saha , Hans Martin Schmid

The aim of this paper is to study the astrometric trajectory of microlensing events with an extended lens and/or source. We consider not only a dark lens but also a luminous lens as well. We find that the discontinuous finite-lens…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 C. -H. Lee , S. Seitz , A. Riffeser , R. Bender