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Related papers: Near-Field Microlensing from Wide-Field Surveys

200 papers

We consider strong gravitational lensing by nearby stars. Using our wave-optical treatment of lensing phenomena, we study Einstein rings that may form around nearby stellar lenses. It is remarkable that these rings are bright and large…

Instrumentation and Methods for Astrophysics · Physics 2023-02-13 Slava G. Turyshev , Viktor T. Toth

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

The current searches for microlensing events towards the galactic bulge can be used to detect planets around the lensing stars. Their effect is a short-term modulation on the smooth lightcurve produced by the main lensing star. Current and…

Astrophysics · Physics 2015-06-24 Joachim Wambsganss

Microlensing events have historically been discovered throughout the Galactic bulge and plane by surveys designed solely for that purpose. We conduct the first multi-year search for microlensing events on the Zwicky Transient Facility…

Astrophysics of Galaxies · Physics 2023-04-26 Michael S. Medford , Natasha S. Abrams , Jessica R. Lu , Peter Nugent , Casey Y. Lam

Simultaneous space- and ground-based microlensing surveys, such as K2's Campaign 9 (K2C9) and $WFIRST$, facilitate measuring the masses and distances of free-floating planet (FFP) candidates. FFPs are identified as single-lens events with a…

Earth and Planetary Astrophysics · Physics 2016-10-05 Calen B. Henderson , Yossi Shvartzvald

Massive stars at cosmological distances can be individually detected during transient microlensing events, when gravitational lensing magnifications may exceed ~1000. Nine such sources were identified in JWST NIRCam imaging of a single…

Simulations of planetary microlensing at high magnification that were carried out on a cluster computer are presented. It was found that the perturbations due to two-thirds of all planets occur in the time interval [-0.5t_FWHM, 0.5t_ FWHM]…

Astrophysics · Physics 2009-11-07 N. J. Rattenbury , I. A. Bond , J. Skuljan , P. C. M. Yock

Gravitational lensing provides a means to measure mass that does not rely on detecting and analysing light from the lens itself. Compact objects are ideal gravitational lenses, because they have relatively large masses and are dim. In this…

Instrumentation and Methods for Astrophysics · Physics 2017-06-15 A. J. Harding , R. Di Stefano , S. Lépine , J. Urama , D. Pham , C. Baker

This study commenced by cross-matching data from the GAIA and OGLE telescopes with the aim of resolving the source star, long after microlensing is finished. The aim is breaking degeneracy between parameters of the microlensing equation,…

Instrumentation and Methods for Astrophysics · Physics 2024-05-28 Saeed Mozaheb , Sohrab Rahvar

Ongoing microlensing surveys have already yielded more than five hundred microlensing events, most of which have been identified in real-time. In this review I present the basic theory and observational status of these surveys. I highlight…

Astrophysics · Physics 2007-05-23 Shude Mao

We investigate properties of astrometric microlensing of distant sources (such as QSOs and radio galaxies) caused by stars in the Galaxy, mainly focusing on application to the VERA (VLBI Exploration of Radio Astrometry) project. Assuming…

Astrophysics · Physics 2009-11-07 Mareki Honma , Tomoharu Kurayama

Following previous suggestions of other researchers, this paper discusses the prospects for astrometric observation of MACHO gravitational microlensing events. We derive the expected astrometric observables for a simple microlensing event…

Astrophysics · Physics 2009-10-30 A. F. Boden , M. Shao , D. Van Buren

With several detections, the technique of gravitational microlensing has proven useful for studying planets that orbit stars at Galactic distances, and it can even be applied to detect planets in neighbouring galaxies. So far, planet…

Astrophysics · Physics 2010-11-02 S. Rahvar , M. Dominik

Microlensing is generally studied in the geometric optics limit. However, diffraction may be important when nearby substellar objects lens occult distant stars. In particular the effects of diffraction become more important as the…

Astrophysics of Galaxies · Physics 2010-10-05 Jeremy S. Heyl

We propose a near-infrared microlensing survey of the central 2 degree field of the Galactic Center, in an attempt to estimate the surface density and mass distribution of distant free-floating brown dwarfs in the bulge and in the disk,…

Astrophysics · Physics 2016-08-30 Hans Zinnecker

The nature and the location of the lenses discovered in the microlensing surveys done so far towards the LMC remain unclear. Motivated by these questions we computed the optical depth for the different intervening populations and the number…

Astrophysics · Physics 2007-05-23 Philippe Jetzer

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…

The luminosity variation of a stellar source due to the gravitational microlensing effect can be considered also if the light rays are defocused (instead of focused) toward the observer. In this case, we should detect a gap instead of a…

We search for signatures of planets in 43 intensively monitored microlensing events that were observed between 1995 and 1999. Planets would be expected to cause a short duration (~1 day) deviation on the smooth, symmetric light curve…