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Related papers: Microlensing events in the Galactic bulge

200 papers

With the steady increase of the sample size of observed microlenses towards the central regions of the Galaxy, the main source of the uncertainty in the lens mass will shift from the simple Poisson noise to the intrinsic non-uniqueness of…

Astrophysics · Physics 2009-10-30 HongSheng Zhao , P. Tim de Zeeuw

Recently, from the Hubble Space Telescope (HST) images of one of the Large Magellanic Cloud (LMC) events taken 6.3 years after the original lensing measurement, Alcock et al. were able to directly image the lens. Although the first resolved…

Astrophysics · Physics 2009-11-07 Cheongho Han , Heon-Young Chang

VISTA variables in the Via Lactea is an ESO Public survey dedicated to scan the bulge and an adjacent portion of the Galactic disk in the fourth quadrant using the VISTA telescope and the near-infrared camera VIRCAM. One of the leading…

Solar and Stellar Astrophysics · Physics 2015-09-23 R. H. Barba , A. Roman-Lopes , J. L. Nilo Castellon , V. Firpo , D. Minniti , P. Lucas , J. P. Emerson , M. Hempel , M. Soto , R. K. Saito

Planet formation theories predict the existence of free-floating planets that have been ejected from their parent systems. Although they emit little or no light, they can be detected during gravitational microlensing events. Microlensing…

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

Estimating the number of microlensing events observed in different parts of the Galactic bulge is a crucial point in planning microlensing experiments. Reliable estimates are especially important if observing resources are scarce, as is the…

Astrophysics of Galaxies · Physics 2015-12-09 R. Poleski

We investigate the effect of blending in future gravitational microlensing surveys by carrying out simulation of Galactic bulge microlensing events to be detected from a proposed space-based lensing survey. From this simulation, we find…

Astrophysics · Physics 2008-11-26 Cheongho Han , Byeong-Gon Park , Ho-Il Kim , Kyongae Chang

The microlensing parallax campaign with the $Spitzer$ space telescope aims to measure masses and distances of microlensing events seen towards the Galactic bulge, with a focus on planetary microlensing events. The hope is to measure how the…

Earth and Planetary Astrophysics · Physics 2020-09-30 Naoki Koshimoto , David P. Bennett

The Galactic bulge at latitude $4<|b|$(deg.)$<10$ was claimed to show an X-shape, which means that stellar density distributions along the line of sight have a double peak. However, this double peak is only observed with the red-clump…

Astrophysics of Galaxies · Physics 2022-10-19 Ž. Chrobáková , M. López-Corredoira , F. Garzón

The observed spectra of the microlensed sources towards the Galactic bulge may be used as a tool for studying the kinematics and extinction effects in the Galactic bulge. In this paper, we first investigate the expected distribution of the…

Astrophysics · Physics 2016-08-30 Stephen R. Kane , Kailash C. Sahu

We show that the small intrinsic spread in luminosities of red clump giants can be used to constrain the differences in the streaming motions of Galatic bulge stars on the near side and those on the far side. We propose two methods to…

Astrophysics · Physics 2009-11-07 Shude Mao , Bohdan Paczynski

Galactic bulges are central to understanding galaxy formation and evolution. Here we report on recent studies using micro-lensing events to obtain spectra of high resolution and moderately high signal-to-noise ratios of dwarf stars in the…

During microlensing events with a small impact parameter, the amplification of the source flux is sensitive to the surface brightness distribution of the source star. Such events provide a means for studying the surface structure of target…

Astrophysics · Physics 2009-10-31 David Heyrovsky , Dimitar Sasselov

Galactic model plays an important role in the microlensing field, not only for analyses of individual events but also for statistics of the ensemble of events. However, the Galactic models used in the field varies, and some are…

Astrophysics of Galaxies · Physics 2021-02-24 Hongjing Yang , Shude Mao , Weicheng Zang , Xiangyu Zhang

We present the analysis of the event OGLE-2017-BLG-1186 from the 2017 Spitzer microlensing campaign. This is a remarkable microlensing event because its source is photometrically bright and variable, which makes it possible to perform an…

Solar and Stellar Astrophysics · Physics 2019-07-26 Shun-Sheng Li , Weicheng Zang , Andrzej Udalski , Yossi Shvartzvald , Daniel Huber , Chung-Uk Lee , Takahiro Sumi , Andrew Gould , Shude Mao , Pascal Fouqué , Tianshu Wang , Subo Dong , Uffe G. Jørgensen , Andrew Cole , Przemek Mróz , Michał K. Szymański , Jan Skowron , Radosław Poleski , Igor Soszyński , Paweł Pietrukowicz , Szymon Kozłowski , Krzysztof Ulaczyk , Krzysztof A. Rybicki , Patryk Iwanek , Jennifer C. Yee , Sebastiano Calchi Novati , Charles A. Beichman , Geoffery Bryden , Sean Carey , B. Scott Gaudi , Calen B. Henderson , Wei Zhu , Michael D. Albrow , Sun-Ju Chung , Cheongho Han , Kyu-Ha Hwang , Youn Kil Jung , Yoon-Hyun Ryu , In-Gu Shin , Sang-Mok Cha , Dong-Jin Kim , Hyoun-Woo Kim , Seung-Lee Kim , Dong-Joo Lee , Yongseok Lee , Byeong-Gon Park , Richard W. Pogge , Ian A. Bond , Fumio Abe , Richard Barry , David P. Bennett , Aparna Bhattacharya , Martin Donachie , Akihiko Fukui , Yuki Hirao , Yoshitaka Itow , Iona Kondo , Naoki Koshimoto , Man Cheung Alex Li , Yutaka Matsubara , Yasushi Muraki , Shota Miyazaki , Masayuki Nagakane , Clément Ranc , Nicholas J. Rattenbury , Haruno Suematsu , Denis J. Sullivan , Daisuke Suzuki , Paul J. Tristram , Atsunori Yonehara , Grant Christie , John Drummond , Jonathan Green , Steve Hennerley , Tim Natusch , Ian Porritt , Etienne Bachelet , Dan Maoz , Rachel A. Street , Yiannis Tsapras , Valerio Bozza , Martin Dominik , Markus Hundertmark , Nuno Peixinho , Sedighe Sajadian , Martin J. Burgdorf , Daniel F. Evans , Roberto Figuera Jaimes , Yuri I. Fujii , Lauri K. Haikala , Christiane Helling , Thomas Henning , Tobias C. Hinse , Luigi Mancini , Penelope Longa-Peña , Sohrab Rahvar , Markus Rabus , Jesper Skottfelt , Colin Snodgrass , John Southworth , Eduardo Unda-Sanzana , Carolina von Essen , Jean-Phillipe Beaulieu , Joshua Blackman , Kym Hill

VISTA Variables in the Via Lactea (VVV) is an ESO public near-infrared variability survey of the Galactic bulge and an adjacent area of the southern mid-plane. It will produce a deep atlas in the ZYJHKs filters, and a Ks-band time-series…

Solar and Stellar Astrophysics · Physics 2011-11-09 I. Dekany , M. Catelan , D. Minniti , the VVV Collaboration

Recently Alard\markcite{alard1996} proposed to detect the shift of a star's image centroid, $\delta x$, as a method to identify the lensed source among blended stars. Goldberg & Wo\'zniak\markcite{goldberg1997} actually applied this method…

Astrophysics · Physics 2009-10-30 Cheongho Han , Youngjin Jeong

We report results from intensive monitoring of two fields on either side of M31,emphasizing microlensing involving stars and masses in M31. These results stem from the three-year VATT/Columbia survey of variability on 3d to 2m timescales.…

The inner Milky Way is dominated by a boxy, triaxial bulge which is believed to have formed through disk instability processes. Despite its proximity, its large-scale properties are still not very well known, due to our position in the…

Astrophysics of Galaxies · Physics 2015-06-16 Christopher Wegg , Ortwin Gerhard

This is a preliminary report on the application of Difference Image Analysis (DIA) to galactic bulge images. The aim of this analysis is to increase the sensitivity to the detection of gravitational microlensing. We discuss how the DIA…