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The two-point complex coherence function constitutes a complete representation for scalar quasi-monochromatic optical fields. Exploiting dynamically reconfigurable slits implemented with a digital micromirror device, we report on…

Moderately close binaries are a special class of targets for planet searches. From a theoretical standpoint, their hospitality to giant planets is uncertain and debated. From an observational standpoint, many of these systems present…

Earth and Planetary Astrophysics · Physics 2015-05-14 A. Eggenberger

Gravitational lensing of luminous matter that surrounds a black hole or some other sufficiently compact object produces an infinite sequence of images. Besides the direct (or primary) image, it comprises demagnified and deformed replicas of…

General Relativity and Quantum Cosmology · Physics 2024-08-21 Fabio Aratore , Oleg Yu. Tsupko , Volker Perlick

Observations of binary stars for faint companions with conventional coronagraphic methods are challenging, as both targets will be bright enough to obscure any nearby faint companions if their scattered light is not suppressed. We propose…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Eric Cady , Michael McElwain , N. Jeremy Kasdin , Christian Thalmann

The challenge for optical detection of terrestial planet is the 25 magnitude brightness contrast between the planet and its host star. This paper introduces a new pupil design that produces a very dark null along its symmetry axis. By…

Astrophysics · Physics 2007-05-23 David N. Spergel

Some modified two-slit interference experiments were carried out showing an apparent paradox in wave-particle duality. In a typical such experiment, the screen, where the interference pattern is supposed to be formed, is replaced by a…

Quantum Physics · Physics 2023-04-05 Tabish Qureshi

Many astrophysical systems can be approximated as isothermal spheres. In an isothermal sphere, the ``foreground'' objects can act as lenses on ``background'' objects in the same distribution. We study gravitational lensing by a singular…

Astrophysics · Physics 2009-12-30 Yun Wang

The CoRoT and Kepler satellites were the first space platforms designed to perform high-precision photometry for a large number of stars. Multiple systems display a wide variety of photometric variability, making them natural benefactors of…

Solar and Stellar Astrophysics · Physics 2016-03-15 John Southworth

Traditional approaches to measuring the stellar mass function (MF) are fundamentally limited because objects are detected based on their luminosity, not their mass. These methods are thereby restricted to luminous and relatively nearby…

Astrophysics · Physics 2009-10-28 Andrew Gould

Photometry of galaxies has typically focused on small, faint systems due to their interest for cosmological studies. Large angular size galaxies, on the other hand, offer a more detailed view into the properties of galaxies, but bring a…

Astrophysics · Physics 2007-05-23 J. Schombert

Due to their extremely small luminosity compared to the stars they orbit, planets outside our own Solar System are extraordinarily difficult to detect directly in optical light. Careful photometric monitoring of distant stars, however, can…

The new astronomical technique of gravitational microlensing enables measurements of high precision to be made in certain circumstances. Useful advances have been made in the fields of galactic astronomy, stellar astronomy and planetary…

Astrophysics · Physics 2017-08-23 Philip Yock

In this paper, a non-Hermitian two-dimensional photonic crystal flat lens is proposed. The negative refraction of the second band of photonic crystal is utilized to realize super-resolution imaging of the point source. Based on the…

Optics · Physics 2019-12-16 Longfei Li , Jianlan Xie , Jianjun Liu

We analyze gravitational lensing, in particular the shadow and photon rings, in the Ernst spacetime, also known as the Schwarzschild-Melvin spacetime, which describes a Schwarzschild black hole immersed in a homogenous magnetic field.…

General Relativity and Quantum Cosmology · Physics 2025-12-30 Muhammad Haider Khan , Volker Perlick

We consider using toroidal curved detectors to improve the performance of imaging optical systems. We demonstrate that some optical systems have an anamorphic field curvature. We consider an unobscured re-imaging three-mirror anastigmat as…

Instrumentation and Methods for Astrophysics · Physics 2018-06-22 Eduard Muslimov , Emmanuel Hugot , Marc Ferrari , Thibault Behaghel , Gerard R. Lemaitre , Melanie Roulet , Simona Lombardo

In this paper are discussed the nulling and imaging properties of monolithic pupil telescopes equipped with a focal plane waveguide array, which could be envisaged as precursor space missions for future nulling interferometers or…

Instrumentation and Methods for Astrophysics · Physics 2015-05-28 Francois Henault

Gravitational microlensing is not achromatic when the star being microlensed is resolved by the lens. We show how narrow-band photometry and moderate- to high-resolution spectroscopy can be used to reconstruct the stellar surface intensity…

Astrophysics · Physics 2007-05-23 Dimitar D. Sasselov

Two-photon absorption is theoretically analyzed within the semiclassical formalism of radiation-matter interaction. We consider an ensemble of inhomogeneously broadened three-level atoms subjected to the action of two counterpropagating…

Quantum Physics · Physics 2007-05-23 I. Perez-Arjona , G. J. de Valcarcel , Eugenio Roldan

We define a 2-normal surface to be one which intersects every 3-simplex of a triangulated 3-manifold in normal triangles and quadrilaterals, with one or two exceptions. The possible exceptions are a pair of octagons, a pair of unknotted…

Geometric Topology · Mathematics 2009-09-29 David Bachman

Distant starlight passing through the Earth's atmosphere is refracted by an angle of just over one degree near the surface. This focuses light onto a focal line starting at an inner (and chromatic) boundary out to infinity - offering an…

Instrumentation and Methods for Astrophysics · Physics 2019-10-09 David Kipping
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