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Related papers: Microlensing events in the Galactic bulge

200 papers

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

Microlensing campaigns have a long history of observations covering the Galactic bulge, where thousands of detections have been obtained, including many exoplanetary systems. The Euclid Galactic Bulge Survey represents a unique opportunity…

The color-magnitude diagrams of $\sim 5\times 10^5$ stars obtained for 13 fields towards the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump stars. We find that the distributions of the…

Astrophysics · Physics 2009-10-22 K. Z. Stanek , M. Mateo , A. Udalski , M. Szymanski , J. Kaluzny , M. Kubiak

The abundance and narrow magnitude dispersion of Red Clump (RC) stars make them a popular candidate for mapping the morphology of the bulge region of the Milky Way. Using an estimate of the RC's intrinsic luminosity function, we extracted…

Astrophysics of Galaxies · Physics 2023-08-10 Brenna Coleman , Dylan Paterson , Chris Gordon , Oscar Macias , Harrison Ploeg

We present detailed maps of the microlensing optical depth and event density over an area of 195 sq. deg towards the Galactic bulge. The maps are computed from synthetic stellar catalogues generated from the Besancon Galaxy Model, which…

Astrophysics · Physics 2015-05-13 E. Kerins , A. C. Robin , D. J. Marshall

We analyze an ensemble of microlensing events from the 2015 Spitzer microlensing campaign, all of which were densely monitored by ground-based high-cadence survey teams. The simultaneous observations from Spitzer and the ground yield…

Microlensing has a unique advantage for detecting dark objects in the Milky Way, such as free-floating planets, neutron stars, and stellar-mass black holes. Most microlensing surveys focus on the Galactic bulge, where higher stellar density…

Astrophysics of Galaxies · Physics 2024-11-11 Ruocheng Zhai , Antonio C. Rodriguez , Shude Mao , Casey Y. Lam , Eric C. Bellm , Josiah Purdum , Frank J. Masci , Avery Wold

Perhaps as many as 30 parallax microlensing events are known, thanks to the efforts of the MACHO, OGLE, EROS and MOA experiments monitoring the bulge. Using Galactic models, we construct mock catalogues of microlensing light curves towards…

Astrophysics · Physics 2009-11-11 M. C. Smith , V. Belokurov , N. W. Evans , S. Mao , J. H. An

Photometry of the Galactic bulge, collected during the OGLE-II microlensing search, indicates high and non-uniform interstellar extinction toward the observed fields. We use the mean I-band magnitude and V-I color of red clump stars as a…

Astrophysics · Physics 2008-11-26 A. Udalski

We describe a new method to search for gravitational microlensing toward the Galactic bulge that employs a small camera rather than a conventional telescope and probes new regions of parameter space. The small aperture (~65 mm) permits…

Astrophysics · Physics 2009-10-30 Andrew Gould , D. L. DePoy

During the months when the galactic bulge is visible from the southern hemisphere, there are typically about 8 to 10 on-going microlensing events at any given time. If the lensing stars have planets around them, then the signature of the…

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

We investigate properties of Galactic microlensing events in which a stellar object is lensed by a neutron star. For an all-sky photometric microlensing survey, we determine the number of lensing events caused by $\sim10^{5}$…

Astrophysics of Galaxies · Physics 2015-07-03 Shi Dai , Martin C. Smith , Mengxiang Lin , Youling Yue , George Hobbs , Renxin Xu

We compute a microlensing map for the Galactic bar. The predicted event rate and event duration distribution are consistent with the $55$ events recently reported by the MACHO and OGLE collaborations. Most of the events are due to lensing…

Astrophysics · Physics 2015-06-24 HongSheng Zhao , R. M. Rich , D. N. Spergel

We present a new EROS-2 measurement of the microlensing optical depth toward the Galactic Bulge. Light curves of $5.6\times 10^{6}$ clump-giant stars distributed over $66 \deg^2$ of the Bulge were monitored during seven Bulge seasons. 120…

Microlensing observations toward globular clusters could be very useful to probe their low mass star and brown dwarf content. Using the large set of microlensing events detected so far toward the Galactic centre we investigated whether for…

Cosmology and Nongalactic Astrophysics · Physics 2013-04-23 Philippe Jetzer

We present the first M31 candidate microlensing events from the Microlensing Exploration of the Galaxy and Andromeda (MEGA) survey. MEGA uses several telescopes to detect microlensing towards the nearby Andromeda galaxy, M31, in order to…

We determine the microlensing event rate distribution, $\Gamma(t_{E})$, that is properly normalized by the first year MACHO group observations (Alcock et al. 1997). By comparing the determined $\Gamma(t_{E})$ with various MF models of lens…

Astrophysics · Physics 2007-05-23 Cheongho Han , Seunghun Lee

Red clump giants in the Galactic bulge are approximate standard candles and hence they can be used as distance indicators. We compute the proper motion dispersions of RCG stars in the Galactic bulge using the proper motion catalogue from…

We use the VVV survey observations in bulge regions close to the Galactic plane to trace the bar inclination at the Galactic latitude b\sim\pm1{\deg} and to investigate a distinct structure in the inner regions of the bar that was…

Astrophysics of Galaxies · Physics 2015-05-30 O. A. Gonzalez , M. Rejkuba , D. Minniti , M. Zoccali , E. Valenti , R. K. Saito

We present the first systematic search for microlensing events with variability in their baselines using data from the third phase of the Optical Gravitational Lensing Experiment (OGLE-III). A total of 137 candidates (88 new) was discovered…