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Related papers: Microlensing of fast and slow compact objects

200 papers

The flux anomalies in four-image gravitational lenses can be interpreted as evidence for the dark matter substructure predicted by cold dark matter (CDM) halo models. In principle, these flux anomalies could arise from alternate sources…

Astrophysics · Physics 2008-11-26 C. S. Kochanek , N. Dalal

A detailed analysis is presented of gravitational microlensing by intervening compact objects of the black hole shadows imaged by the Event Horizon Telescope (EHT). We show how the center, size, and shape of the shadow depend on the…

Astrophysics of Galaxies · Physics 2024-05-14 Himanshu Verma , Joseph Silk

We search for gravitational wave (GW) events from LIGO-Virgo's third run that may have been affected by gravitational lensing. Gravitational lensing delays the arrival of GWs, and alters their amplitude -- thus biasing the inferred…

The phase transition responsible for axion dark matter production can create large amplitude isocurvature perturbations which collapse into dense objects known as axion miniclusters. We use microlensing data from the EROS survey, and from…

Cosmology and Nongalactic Astrophysics · Physics 2017-07-19 Malcolm Fairbairn , David J. E. Marsh , Jérémie Quevillon

We consider small-scale spheroidal clusters of weakly interacting massive particles in our Galaxy as non-compact gravitational microlenses and predict the appearance of caustics in the plane of a lensed source. The crossing of these…

Astrophysics · Physics 2010-04-30 M. B. Bogdanov , A. M. Cherepashchuk

We show that dark matter substructure in galaxy-scale halos perturbs the time delays between images in strong gravitational lens systems. The variance of the effect depends on the subhalo mass function, scaling as the product of the…

Astrophysics · Physics 2011-02-11 Charles R. Keeton , Leonidas A. Moustakas

To generate the standard microlensing light curve one assumes that the relative motion of the source, the lens, and the observer is linear. In reality, the relative motion is likely to be more complicated due to accelerations of the…

Astrophysics · Physics 2009-11-07 M. C. Smith , S. Mao , B. Paczynski

Interferometric observations of gravitational microlensing events offer an opportunity for precise, efficient, and direct mass and distance measurements of lensing objects, especially those of isolated neutron stars and black holes.…

The gravitational microlensing technique allows the discovery of exoplanets around stars distributed in the disk of the galaxy towards the bulge. However, the alignment of two stars that led to the discovery is unique over the timescale of…

Earth and Planetary Astrophysics · Physics 2015-12-09 I. Boisse , A. Santerne , J. -P. Beaulieu , W. Fakhardji , N. C. Santos , P. Figueira , S. G. Sousa , C. Ranc

The abundance of protoplanetary bodies ejected from their parent star system is presently poorly-constrained. With only two existing optical observations of interstellar objects in the $10^{8} - 10^{10}$ kg mass range and a small number of…

Earth and Planetary Astrophysics · Physics 2023-12-22 William DeRocco , Nolan Smyth , Stefano Profumo

In this article we review the astrophysical application of gravitational microlensing. After introducing the history of gravitational lensing, we present the key equations and concept of microlensing. The most frequent microlensing events…

Instrumentation and Methods for Astrophysics · Physics 2016-03-21 Sohrab Rahvar

The density of stars and MACHOs in the universe could theoretically be determined or limited by simultaneous measurements of compact sources by well separated observers. A gravitational lens effect would be expected to create a slight…

Astrophysics · Physics 2009-10-30 Robert J. Nemiroff

Studies of gravitational microlensing effects require the estimation of their detection efficiency as soon as one wants to quantify the massive compact objects along the line of sight of source targets. This is particularly important for…

Astrophysics of Galaxies · Physics 2023-10-11 Tristan Blaineau , Marc Moniez

If it is hypothesised that there is no dark matter then some alternative gravitational theory must take the place of general relativity (GR) on the largest scales. Dynamical measurements can be used to investigate the nature of such a…

Astrophysics · Physics 2008-11-26 Daniel J. Mortlock , Edwin L. Turner

Gravitational lensing causes the distribution of observed brightnesses of standard candles at a given redshift to be highly non-gaussian. The distribution is strongly, and asymmetrically, peaked at a value less than the expected value in a…

Astrophysics · Physics 2009-10-30 Daniel E. Holz

Dark Matter (DM) halos with masses below $\sim10^{8}$ $M_{\odot}$, which would help to discriminate between DM models, may be detected through their gravitational effect on distant sources. The same applies to primordial black holes,…

One of the frontiers for advancing what is known about dark matter lies in using strong gravitational lenses to characterize the population of the smallest dark matter halos. There is a large volume of information in strong gravitational…

Cosmology and Nongalactic Astrophysics · Physics 2023-09-01 Ryan E. Keeley , Anna M. Nierenberg , Daniel Gilman , Simon Birrer , Andrew Benson , Tommaso Treu

Weak gravitational lensing observations probe the spectrum and evolution of density fluctuations and the cosmological parameters which govern them but are currently limited to small fields and subject to selection biases. We show how the…

Astrophysics · Physics 2009-10-31 Asantha Cooray , Wayne Hu , Jordi Miralda-Escude

We show how observations of multiply-imaged quasars at high redshift can be used as a probe of dark matter clumps (subhalos with masses ~ 10^9 solar masses) within the virialized extent of more massive lensing halos. A large abundance of…

Astrophysics · Physics 2015-06-24 R. Benton Metcalf , Piero Madau

We calculate the abundance of dark-matter concentrations that are sufficiently overdense to produce a detectable weak-gravitational-lensing signal. Most of these overdensities are virialized halos containing identifiable X-ray and/or…

Astrophysics · Physics 2009-11-07 Nevin N. Weinberg , Marc Kamionkowski