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Related papers: Dark matter millilensing and VSOP-2

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We study the abundance of substructure in the matter density near galaxies using ALMA Science Verification observations of the strong lensing system SDP.81. We present a method to measure the abundance of subhalos around galaxies using…

We present the results of a study of weak lensing by galaxies based on 45.5 deg$^2$ of $R_C$ band imaging data from the Red-Sequence Cluster Survey (RCS). We present the first weak lensing detection of the flattening of galaxy dark matter…

Astrophysics · Physics 2008-11-26 Henk Hoekstra , Howard K. C. Yee , Michael D. Gladders

The standard paradigm of hierarchical structure formation in a LambdaCDM universe predicts the presence of dark matter subhaloes, hosted by Milky Way-sized galaxies. Anticipated subhalo masses range from 10^{10} down to a cut-off mass…

High Energy Astrophysical Phenomena · Physics 2012-06-25 H. -S. Zechlin , M. V. Fernandes , D. Elsaesser , D. Horns

The dark matter halo has non-negligible effects on the gravitational lensing of supermassive black hole in the galaxy center. Our work presents a study on the time-delay of light in gravitational lensing of black holes enclosed by dark…

General Relativity and Quantum Cosmology · Physics 2024-10-14 Chen-Kai Qiao , Ping Su

We propose a new technique to directly measure the shapes of dark matter halos of galaxies using weak gravitational lensing. Extending the standard galaxy-galaxy lensing method, we show that the shape parameters of the mass distribution of…

Astrophysics · Physics 2009-10-31 Priyamvada Natarajan , Alexandre Refregier

Major progresses have been made this last year towards a better knowledge of the invisible mass. Michel Spiro will talk in details about the micro-lensing experiments and their promising results; the ROSAT satellite has provided extended…

Astrophysics · Physics 2007-05-23 F. Combes , D. Pfenniger

After decades of searching, the true nature of dark matter still eludes us. One potential probe of the form of dark matter in galaxy clusters is to search for microlensing variability in the giant arcs and arclets. In this paper, a simple…

Astrophysics · Physics 2007-05-23 Artem Tuntsov , Geraint Lewis , Rodrigo Ibata , Jean-Paul Kneib

The annihilation of dark matter particles in the centers of minihalos may lead to the formation of so-called dark stars, which are cooler, larger, more massive and potentially more long-lived than conventional population III stars. Here, we…

Cosmology and Nongalactic Astrophysics · Physics 2015-03-17 E. Zackrisson

Strong gravitational lensing can be used to find otherwise invisible dark matter subhaloes. In such an analysis, the lens galaxy mass model is a significant source of systematic uncertainty. In this paper we analyse the effect of angular…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-15 Conor M. O'Riordan , Simona Vegetti

We assess how much unused strong lensing information is available in the deep \emph{Hubble Space Telescope} imaging and VLT/MUSE spectroscopy of the \emph{Frontier Field} clusters. As a pilot study, we analyse galaxy cluster…

Cosmology and Nongalactic Astrophysics · Physics 2018-04-25 M. Jauzac , D. Harvey , R. Massey

MAssive Compact Halo Objects such as brown dwarfs, Jupiters, and black holes are prime candidates to comprise the dark halo of our galaxy. Paczynski noted that objects (dubbed MACHOs) with masses in the range $10^{-6}M_\odot < M \simlt 100…

Astrophysics · Physics 2009-10-22 D. P. Bennett

Coulomb-like interactions typically has a cross section scales with velocity dependence as $\sigma=\sigma_0 v^{-4}$. The momentum transfer rate between a slightly charged dark matter and ionized particles increases significantly at low…

Cosmology and Nongalactic Astrophysics · Physics 2023-11-21 Yugen Lin , Yu Gao

A variety of observational campaigns seek to test dark-matter models by measuring dark-matter subhaloes at low masses. Despite their predicted lack of stars, these subhaloes may be detectable through gravitational lensing or via their…

Astrophysics of Galaxies · Physics 2023-07-20 Megan Barry , Andrew Wetzel , Sierra Chapman , Jenna Samuel , Robyn Sanderson , Arpit Arora

Microlensing surveys search for the transient brightening of a background star that is the signature of gravitational lensing by a foreground compact object. This technique is an elegant way to search for astrophysical candidates that might…

Astrophysics · Physics 2007-05-23 Christopher W. Stubbs

In cold dark matter models, a galaxy's dark matter halo is more spatially extended than its stars. However, even though the five well-constrained gravitational lenses with time delay measurements must have similar dark matter distributions,…

Astrophysics · Physics 2007-05-23 C. S. Kochanek

The nature of dark matter is poorly constrained on subgalactic scales. Alternative models to cold dark matter, such as warm dark matter or self-interacting dark matter, could produce very different dark haloes on these scales. One of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-11-14 Wolfgang J. R. Enzi , Coleman M. Krawczyk , Daniel J. Ballard , Thomas E. Collett

Weak gravitational lensing is now established as a powerful method to measure mass fluctuations in the universe. It relies on the measurement of small coherent distortions of the images of background galaxies. Even low-level correlations in…

Astrophysics · Physics 2009-07-09 Alan Heavens , Alexandre Refregier , Catherine Heymans

We study the reliability of dark-matter halo detections with three different linear filters applied to weak-lensing data. We use ray-tracing in the multiple lens-plane approximation through a large cosmological simulation to construct…

The MACHO project has been monitoring about ten million stars in the Large Magellanic Cloud in the search for gravitational microlensing events caused by massive compact halo objects (Machos) in the halo of the Milky Way. In our standard…

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