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Related papers: Microlensing and Galactic Structure

200 papers

Microlensing has established itself as a powerful new method for the detection of baryonic dark matter in the Galaxy. The theory of microlensing is sketched and its similarity with the optical effect of twinkling is explained. The bulk of…

Astrophysics · Physics 2007-05-23 Wyn Evans

The spatial distribution of compact dark matter in our Galaxy can be determined in a few years of monitoring Galactic globular clusters for microlensing. Globular clusters are the only dense fields of stars distributed throughout the…

Astrophysics · Physics 2009-10-30 James E. Rhoads , Sangeeta Malhotra

The microlensing probability (optical depth $\tau$) toward the Galactic center carries information about the mass distribution of the Galactic bulge/bar, so can be used to constrain the very uncertain shape parameters of the bar. We find…

Astrophysics · Physics 2015-06-24 HongSheng Zhao , Shude Mao

More reliable constraints on the microlensing optical depth comes from a better understanding of the Galactic model. Based on well-constrained Galactic bulge and disk models constructed from survey observations, such as, HST, 2MASS, and…

Astrophysics · Physics 2009-11-13 Yoon-Hyun Ryu , Heon-Young Chang , Myeong-Gu Park , Ki-Won Lee

Gravitational microlensing is currently the only technique that helps study the Galactic distribution of planets as a function of distance from the Galactic center. The Galactic location of a lens system can be uniquely determined only when…

Earth and Planetary Astrophysics · Physics 2021-09-08 Naoki Koshimoto , David P. Bennett , Daisuke Suzuki , Ian A. Bond

A high optical depth to gravitational microlensing towards the galactic bulge is consistent with current models of the galactic bar. The low optical depth towards the LMC can probably be accounted for by the ordinary stars in our galaxy and…

Astrophysics · Physics 2016-08-30 Bohdan Paczynski

It has been known that recent microlensing results towards the bulge imply mass densities that are surprisingly high given dynamical constraints on the Milky Way mass distribution. We derive the maximum optical depth towards the bulge that…

Astrophysics · Physics 2009-10-30 Konrad Kuijken

Gravitational microlensing is a unique probe of the stellar content in strong lens galaxies. Flux ratio anomalies from gravitationally lensed supernovae (glSNe), just like lensed quasars, can be used to constrain the stellar mass fractions…

Astrophysics of Galaxies · Physics 2025-04-01 Luke Weisenbach , Thomas Collett , Wolfgang Enzi , Lindsay Oldham , Ana Sainz de Murieta

We explore the mass distribution of material associated with galaxies from the observation of gravitational weak lensing for the galaxy mass correlation function with the aid of $N$-body simulations of dark matter. The latter is employed to…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-28 Shogo Masaki , Masataka Fukugita , Naoki Yoshida

We propose a new method that can be used to constrain the properties of the Galactic bar (bulge). If the majority of the lensing objects are in the Galactic bar, then we predict a systematic offset in the apparent magnitude between lensed…

Astrophysics · Physics 2009-10-22 K. Z. Stanek

Large scale structure measurements require accurate and precise knowledge of the survey depth --- typically expressed in the form of a limiting magnitude --- as a function of position on the sky. To date, most surveys only compute the…

Instrumentation and Methods for Astrophysics · Physics 2015-09-04 E. S. Rykoff , E. Rozo , R. Keisler

The number and properties of observed gravitational microlensing events depend on the distribution and kinematics of stars and other compact objects along the line of sight. In particular, precise measurements of the microlensing optical…

If compact baryonic objects contribute significantly to the dark matter in our Galaxy, their mass function will present vital clues for galaxy formation theories and star formation processes in the early Universe. Here we discuss what one…

Astrophysics · Physics 2008-11-26 E. J. Kerins , B. J. Carr

The color-magnitude diagrams of $\sim 7 \times 10^5$ stars obtained for 12 fields across the Galactic bulge with the OGLE project reveal a well-defined population of bulge red clump giants. We find that the distributions of the apparent…

Astrophysics · Physics 2009-10-28 K. Z. Stanek , A. Udalski , M. Szymanski , J. Kaluzny , M. Kubiak , M. Mateo , W. Krzeminski

We generalize to elliptical models the argument of Kuijken (1997), which connects the microlensing optical depth towards the Galactic bulge to the Galactic rotation curve. When applied to the latest value from the MACHO collaboration for…

Astrophysics · Physics 2009-10-31 James Binney , Nicolai Bissantz , Ortwin Gerhard

A long-standing problem in astrophysics is to measure the mass associated with galaxies. Gravitational lensing provides one of the cleanest ways to make this measurement. To date, the most powerful lensing probes of galactic mass have been…

Astrophysics · Physics 2009-09-29 Scott Dodelson , Glenn D. Starkman

Present-day multi-wavelength deep imaging surveys allow to characterise the outskirts of galaxies with unprecedented precision. Taking advantage of this situation, we define a new physically motivated measurement of size for galaxies based…

Astrophysics of Galaxies · Physics 2020-02-05 Ignacio Trujillo , Nushkia Chamba , Johan H. Knapen

Gravitational lensing has now become a popular tool to measure the mass distribution of structures in the Universe on various scales. Here we focus on the study of galaxy's scale dark matter halos with galaxy-galaxy lensing techniques:…

Astrophysics · Physics 2007-05-23 M. Limousin , J-P. Kneib , P. Natarajan

Stringent observational constraints on the sub-galactic matter power spectrum would allow one to distinguish between the concordance $\Lambda$CDM and the various alternative dark-matter models that predict significantly different properties…

Astrophysics of Galaxies · Physics 2023-06-21 D. Bayer , S. Chatterjee , L. V. E. Koopmans , S. Vegetti , J. P. McKean , T. Treu , C. D. Fassnacht , K. Glazebrook

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
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