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In this paper, we review the various ways in which an infrared stellar interferometer can be used to perform direct detection of extrasolar planetary systems. We first review the techniques based on classical stellar interferometry, where…

Instrumentation and Methods for Astrophysics · Physics 2015-03-17 O. Absil

Astrometry is a powerful technique in astrophysics to measure three-dimensional positions of stars and other astrophysical objects, including exoplanets and the gravitational influence they have on each other. Interferometric astrometry is…

Instrumentation and Methods for Astrophysics · Physics 2018-12-10 Michael J. Ireland , Julien Woillez

The speckle imaging is a photographic technique that resolves objects viewed through severely distorted media. The results are insensitive to the errors caused by apparent size of the isoplanatic patch and the telescope aberrations. In this…

Astrophysics · Physics 2007-05-23 S K Saha

Astronomers usually need the highest angular resolution possible, but the blurring effect of diffraction imposes a fundamental limit on the image quality from any single telescope. Interferometry allows light collected at widely-separated…

Instrumentation and Methods for Astrophysics · Physics 2015-05-20 John D. Monnier , Ronald J. Allen

Context: Some stellar objects exhibit very narrow spectral lines in the visible range additional to their blackbody radiation. Natural lasing has been suggested as a mechanism to explain narrow lines in Wolf-Rayet stars. However, the…

Instrumentation and Methods for Astrophysics · Physics 2017-05-26 Peng Kian Tan , Christian Kurtsiefer

A new theoretical technique for understanding, analyzing and developing optical systems is presented. The approach is statistical in nature, where information about an object under investigation is discovered, by examining deviations from a…

Optics · Physics 2016-09-20 Damien P. Kelly

An explicit expression is given for the correlation function of blinking systems, i.e. systems exhibiting light and dark periods in their fluorescence. We show through the example of terrylene in a crystalline host that it is possible to…

Quantum Physics · Physics 2009-11-10 Gerhard C. Hegerfeldt , Dirk Seidel

Bandwidth smearing is a chromatic aberration due to the finite frequency bandwidth. In long-baseline optical interferometry terms, it is when the angular extension of the source is greater than the coherence length of the interferogram. As…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Régis Lachaume , Jean-Philippe Berger

The space-time correlations of streams of photons can provide fundamentally new channels of information about the Universe. Today's astronomical observations essentially measure certain amplitude coherence functions produced by a source.…

Instrumentation and Methods for Astrophysics · Physics 2009-03-03 C. Barbieri , M. K. Daniel , W. J. de Wit , D. Dravins , H. Jensen , P. Kervella , S. Le Bohec , F. Malbet , P. Nunez , J. P. Ralston , E. N. Ribak

As first demonstrated by Hanbury Brown and Twiss, it is possible to observe interference between independent light sources by measuring correlations in their intensities rather than their amplitudes. In this work, we apply this concept of…

Quantum Physics · Physics 2023-07-07 G. S. Thekkadath , D. England , F. Bouchard , Y. Zhang , M. S. Kim , B. Sussman

A new method for separating intensity variations of a source's radio emission having various physical natures is proposed. The method is based on a joint analysis of the structure function of the intensity variations and the asymmetry…

Astrophysics · Physics 2009-11-11 V. I. Shishov , T. V. Smirnova

We consider a method for obtaining information on polarization of astronomical objects radiation at diffraction limited resolution - differential speckle polarimetry. As an observable we propose to use averaged cross spectrum of two…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 Boris Safonov

I present a discussion of fundamental stellar parameters and their observational determination in the context of interferometric measurements with current and future optical/infrared interferometric facilities. Stellar parameters and the…

Astrophysics · Physics 2007-05-23 M. Wittkowski

A new, different kind of intensity correlation, denoted as polarization based intensity correlation, is proposed and investigated to study the correlation between different polarization components of polarization speckle, which has…

Optics · Physics 2019-11-20 Abhijit Roy , Maruthi M. Brundavanam

In the 1950's Hanbury Brown and Twiss showed that one could measure the angular sizes of astronomical radio sources and stars from correlations of signal intensities, rather than amplitudes, in independent detectors. Their subsequent…

Nuclear Theory · Physics 2009-09-25 Gordon Baym

In this Letter we propose a fundamental test for probing the thermal nature of the spectrum emitted by sonoluminescence. We show that two-photon correlations can in principle discriminate between real thermal light and the quasi-thermal…

Quantum Physics · Physics 2009-10-31 Francesco Belgiorno , Stefano Liberati , Matt Visser , Dennis Sciama

A technique is presented for treating strongly nonstationary and transient processes in optics, permitting one to take into account both types of competing with each other effects, quantum as well as coherent. The main equations for…

Condensed Matter · Physics 2015-06-24 V. I. Yukalov

Reflectometry is a technique that uses the light reflected by a sample to determine properties of the sample. Interferometric reflectometry uses interference between two beams, one of which is incident on ---and reflected back by--- a…

Optics · Physics 2019-10-10 Alexander Nahmad-Rohen , Wolfgang Langbein

The accuracy with which humans can detect small chromatic differences varies throughout color space. For example, we are far more precise when discriminating two similar orange stimuli than two similar green stimuli. In order for two colors…

Neurons and Cognition · Quantitative Biology 2016-11-23 Maria da Fonseca , Ines Samengo

Atom interferometers measure quantum interference patterns in the wave functions of cold atoms that follow superpositions of different space-time trajectories. These can be sensitive to phase shifts induced by fundamental physics processes…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-16 Oliver Buchmueller , John Ellis , Ulrich Schneider