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Related papers: Probing the optical depth with galaxy number count…

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In recent years, it has become possible to detect individual dark matter subhalos near images of strongly lensed extended background galaxies. Typically, only the most massive subhalos in the strong lensing region may be detected this way.…

Cosmology and Nongalactic Astrophysics · Physics 2016-12-07 Yashar Hezaveh , Neal Dalal , Gilbert Holder , Theodore Kisner , Michael Kuhlen , Laurence Perreault Levasseur

We present the analysis of the first two years of the OGLE search for gravitational lenses towards the Galactic bulge. We detected 9 microlensing events in an algorithmic search of $ \sim 10^8 $ measurements of $ \sim 10^6 $ stars. The…

In this review, I discuss the use of galaxy-galaxy weak lensing measurements to study the masses of dark matter halos in which galaxies reside. After summarizing how weak gravitational lensing measurements can be interpreted in terms of…

Astrophysics of Galaxies · Physics 2015-06-23 Rachel Mandelbaum

Star-forming galaxies which are too faint to be detected individually produce intensity fluctuations in the cosmic background light. This contribution needs to be taken into account as a foreground when using the primordial signal to…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-03 Han-Seek Kim , C. G. Lacey , S. Cole , C. M. Baugh , C. S. Frenk , G. Efstathiou

Optical and infrared observations have thus far detected more celestial cataclysms than have been seen in gravity waves (GW). This argues that we should search for gravity wave signatures that correspond to flux variability seen at optical…

Astrophysics · Physics 2009-02-05 Christopher W. Stubbs

We compare galaxy number counts in HST/ACS fields containing moderate-redshift (0.2<z<1.0) strong gravitational lenses with those in two control samples: (1) the first square degree of the COSMOS survey, comprising 259 ACS fields and (2) 20…

Cosmology and Nongalactic Astrophysics · Physics 2011-04-07 C. D. Fassnacht , L. V. E. Koopmans , K. C. Wong

Multiply-imaged quasar lenses can be used to constrain the substructure mass fraction in galaxy-sized dark matter halos via anomalous flux ratios in lensed images. The flux ratios, however, can be affected by both the substructure in the…

Astrophysics · Physics 2008-11-26 Jacqueline Chen , Andrey V. Kravtsov , Charles R. Keeton

This paper details a description of the pattern of galaxy image distortion over the entire sky caused by the gravitational lensing which is the result of large scale inhomogeneities in our universe. We present a tensor spherical harmonic…

Astrophysics · Physics 2007-05-23 Albert Stebbins

We derive all contributions to the dispersion measure (DM) of electromagnetic pulses to linear order in cosmological perturbations, including both density fluctuations and relativistic effects. We then use this result to calculate the power…

Cosmology and Nongalactic Astrophysics · Physics 2021-06-30 David Alonso

Strong gravitational lensing is a powerful probe of the distribution of matter on sub-kpc scales. It can be used to test the existence of completely dark subhalos surrounding galaxies, as predicted by the standard cold dark matter model, or…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-30 Ioana A. Zelko , Anna M. Nierenberg , Tommaso Treu

Observations of redshift-space distortions in spectroscopic galaxy surveys offer an attractive method for observing the build-up of cosmological structure. In this paper we develop and test a new statistic based on anisotropies in the…

Astrophysics · Physics 2009-11-13 Will J Percival , Martin White

Intrinsic alignments of galaxies are recognised as one of the most important systematic in weak lensing surveys on small angular scales. In this paper we investigate ellipticity correlation functions that are measured separately on…

Cosmology and Nongalactic Astrophysics · Physics 2020-03-04 Tim M. Tugendhat , Robert Reischke , Bjoern Malte Schaefer

A stochastic gravitational wave background causes the apparent positions of distant sources to fluctuate, with angular deflections of order the characteristic strain amplitude of the gravitational waves. These fluctuations may be detectable…

Cosmology and Nongalactic Astrophysics · Physics 2012-11-28 Laura G. Book , Éanna É. Flanagan

Weak gravitational lensing is a unique probe of the dark side of the universe: it provides a direct way to map the distribution of dark matter around galaxies, clusters of galaxies and on cosmological scales. Furthermore, the measurement of…

Astrophysics · Physics 2010-01-07 Henk Hoekstra , Bhuvnesh Jain

Studies of weak gravitational lensing by large-scale structures require the measurement of the distortions introduced to the shapes of distant galaxies at the few percent level by anisotropic light deflection along the line of sight. To…

Astrophysics · Physics 2009-11-07 Andrew W. Blain

Astrometric weak gravitational lensing is a powerful probe of the distribution of matter on sub-Galactic scales, which harbor important information about the fundamental nature of dark matter. We propose a novel method that utilizes angular…

Cosmology and Nongalactic Astrophysics · Physics 2020-07-29 Siddharth Mishra-Sharma , Ken Van Tilburg , Neal Weiner

It is shown that, in addition to the Thomson scattering, the absorption due to the electron-electron, electron-ion and the electron -atom collisions in a partially ionized cosmic plasma would also contribute to the optical depth of the…

Cosmology and Nongalactic Astrophysics · Physics 2009-09-02 V. Krishan

In recent years, gravitational lensing has been used as a means to detect substructure in galaxy-sized halos, via anomalous flux ratios in quadruply-imaged lenses. In addition to causing anomalous flux ratios, substructure may also perturb…

Astrophysics · Physics 2011-02-11 Jacqueline Chen , Eduardo Rozo , Neal Dalal , James E. Taylor

Astrometry -- the precise measurement of positions and motions of celestial objects -- has emerged as a promising avenue for characterizing the dark matter population in our Galaxy. By leveraging recent advances in simulation-based…

Cosmology and Nongalactic Astrophysics · Physics 2022-01-06 Siddharth Mishra-Sharma

Gravitational weak lensing by large scale structures is view as a tool to probe the bias relation between the mass and the light distributions. It is explained how a particular statistic can be used to deproject the 2D mass distribution…

Astrophysics · Physics 2007-05-23 L. Van Waerbeke