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Related papers: Flux Ratio Anomalies: Micro- and Milli-lensing

200 papers

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

Promising methods for studying galaxy evolution rely on optical emission line width measurements to compare intermediate-redshift objects to galaxies with equivalent masses at the present epoch. However, emission lines can be misleading. We…

Astrophysics · Physics 2009-11-07 Elizabeth Barton Gillespie , Liese van Zee

A new type of resonant light absorption by a small particle (nanocluster) is reported. The problem cannot be described within the commonly used dipole scattering approximation and should be studied with methods based upon the exact Mie…

Optics · Physics 2016-09-08 Michael I. Tribelsky

We investigate $HST$/ACS and WFPC2 images at the positions of five candidate microlensing events from a large survey of variability in M31 (MEGA). Three closely match unresolved sources, and two produce only flux upper limits. All are…

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

We report an unexpected variation in the positional offset distributions between Herschel-ATLAS sub-millimetre (submm) sources and their optical associations, depending on both 250-{\mu}m signal-to-noise ratio and 250/350-{\mu}m colour. We…

In this paper, we show that the pattern of microlensing light curve anomalies induced by multiple planets are well described by the superposition of those of the single-planet systems where the individual planet-primary binary pairs act as…

Astrophysics · Physics 2009-11-06 Cheongho Han , Heon-Young Chang , Jin H. An , Kyongae Chang

A small subset of young stellar objects (YSOs) exhibit "see-saw" temporal variations in their mid-infrared SED; as the flux short-ward of a fulcrum wavelength ($\lambda_{f}$) increases the flux long-wards of this wavelength decreases (and…

Earth and Planetary Astrophysics · Physics 2019-09-25 Geoffrey R. Bryan , Sarah T. Maddison , Kurt Liffman

The recent discovery of pulsating ultra-luminous X-ray sources (ULXs) shows that the apparent luminosity of accreting neutron stars (NSs) can exceed the Eddington luminosity by a factor of hundreds. The relation between the actual and…

High Energy Astrophysical Phenomena · Physics 2020-12-16 Alexander A. Mushtukov , Simon Portegies Zwart , Sergey S. Tsygankov , Dmitrij I. Nagirner , Juri Poutanen

Several recent studies show that bright, intermediate and high redshift optically and radio selected QSOs are positively correlated with nearby galaxies on a range of angular scales up to a degree. Obscuration by unevenly distributed…

Astrophysics · Physics 2009-10-31 Liliya L. R. Williams

We present a new technique for monitoring microlensing activity even in highly crowded fields, and use this technique to place limits on low-mass MACHOs in the haloes of M31 and the Galaxy. Unlike present Galactic microlensing surveys, we…

Astrophysics · Physics 2009-09-28 Austin B. Tomaney , Arlin P. S. Crotts

More than half of the volume of our Universe is occupied by cosmic voids. The lensing magnification effect from those under-dense regions is generally thought to give a small dimming contribution: objects on the far side of a void are…

Cosmology and Nongalactic Astrophysics · Physics 2013-01-18 Krzysztof Bolejko , Chris Clarkson , Roy Maartens , David Bacon , Nikolai Meures , Emma Beynon

A standard method to study the mass distribution in galaxy clusters is through strong lensing of background galaxies in which the positions of multiple images of the same source constrain the surface mass distribution of the cluster.…

Cosmology and Nongalactic Astrophysics · Physics 2012-01-26 Ole Host

A comprehensive new approach is presented for deriving probability densities of physical properties characterizing lens or source that constitute an observed galactic microlensing event. While previously encountered problems are overcome,…

Astrophysics · Physics 2009-11-11 M. Dominik

Working by analogy, we use the description of light fluctuations due to random collisions of the radiating atoms to figure out why the reduction of the coherence for light propagating a cosmological distance in the fluctuating background…

General Relativity and Quantum Cosmology · Physics 2016-12-30 Michael Maziashvili

We examine scatter and bias in weak lensing selected clusters, employing both an analytic model of dark matter haloes and numerical mock data of weak lensing cluster surveys. We pay special attention to effects of the diversity of dark…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-04 Takashi Hamana , Masamune Oguri , Masato Shirasaki , Masanori Sato

We re-examine the technique of determining the redshifts of galaxies from the ratio of the submillimeter-to-radio continuum flux densities based on a recently published catalog of 850~$\mu$m sources. We derived the expected variation of…

Astrophysics · Physics 2015-06-24 T. N. Rengarajan , Tsutomu T. Takeuchi

Cosmic superstring loops within the galaxy microlens background point sources lying close to the observer-string line of sight. For suitable alignments, multiple paths coexist and the (achromatic) flux enhancement is a factor of two. We…

Cosmology and Nongalactic Astrophysics · Physics 2014-06-11 Jolyon K. Bloomfield , David F. Chernoff

The possibility that a fraction of the dark matter is comprised of massive compact halo objects (MACHOs) remains unclear, especially in the 20-100 $M_{\odot}$ window. MACHOs could make up binaries, whose mergers may be detected by LIGO as…

Cosmology and Nongalactic Astrophysics · Physics 2018-06-13 Y. K. Wang , F. Y. Wang

Most treatments of large scale anomalies in the microwave sky are a posteriori, with unquantified look-elsewhere effects. We contrast these with physical models of specific inhomogeneities in the early universe which then generate apparent…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-07 Grigor Aslanyan , Richard Easther