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200 papers

This chapter discusses the use and possibilities of optical and infrared interferometry to study star formation. The chapter starts with a brief overview of the star formation process and highlights the open questions from an observational…

Solar and Stellar Astrophysics · Physics 2015-11-20 Rene Oudmaijer , Willem-Jan de Wit

Scattering obscures information carried by wave by producing a speckle pattern, posing a common challenge across various fields, including microscopy and astronomy. Traditional methods for extracting information from speckles often rely on…

We carried out an experimental set-up for reading a hidden drawing under papyrus using an optical technique based on the speckle phenomenon that is observed when a rough surface is illuminated by laser light. We propose the use of several…

Image and Video Processing · Electrical Eng. & Systems 2023-03-23 L. Buffarini , H. J. Rabal , N. L. Cap , E. E. Grumel , M. Trivi , M. Tebaldi

Since pioneering works of Hanbury-Brown and Twiss, intensity-intensity correlations have been widely used in astronomical systems, for example to detect binary stars. They reveal statistics effects and two-particle interference, and offer a…

Interferometry provides one of the possible routes to ultra-high angular resolution for X-ray and gamma-ray astronomy. Sub-micro-arc-second angular resolution, necessary to achieve objectives such as imaging the regions around the event…

Instrumentation and Methods for Astrophysics · Physics 2009-07-31 G. K. Skinner , J. F. Krizmanic

Wireless signals are integral to modern society, enabling both communication and increasingly, environmental sensing. While various propagation models exist, ranging from empirical methods to full-wave simulations, the phenomenon of…

Signal Processing · Electrical Eng. & Systems 2025-09-10 Anurag Pallaprolu , Winston Hurst , Yasamin Mostofi

Techniques like speckle holography and shearography are rarely applied due to the complexity of instrument setup and lack of automated result analysis, despite their potential. By simulating speckle interferometric outcomes, we seek to…

Optics · Physics 2025-11-25 Jessica Plassmann , Michael Schuth , Georg von Freymann

A long-held vision has been to realize diffraction-limited optical aperture synthesis over kilometer baselines. This will enable imaging of stellar surfaces and their environments, and reveal interacting gas flows in binary systems. An…

Instrumentation and Methods for Astrophysics · Physics 2015-08-12 Dainis Dravins , Tiphaine Lagadec , Paul D. Nuñez

Matter-wave interferometry has been largely studied in the last few years. Usually, the main problem in the analysis of the diffraction experiments is to establish the causes for the loss of coherence observed in the interference pattern.…

Quantum Physics · Physics 2008-11-26 Paula I. Villar , Fernando C. Lombardo

The optical elements comprised of sub-diffractive light scatterers, or metasurfaces, hold a promise to reduce the footprint and unfold new functionalities of optical devices. A particular interest is focused on metasurfaces for manipulation…

This is the first article in a series of three dealing with the exploitation of speckle for imaging purposes. Speckle is the complex interference wave-field produced by a random distribution of un-resolved scatterers. In this paper, we show…

Applied Physics · Physics 2026-02-06 Elsa Giraudat , Flavien Bureau , William Lambert , Mathias Fink , Alexandre Aubry

The following exercises aim to learn the link between the object intensity distribution and the corresponding visibility curves of a long-baseline ptical interferometer. They are also intended to show the additional constraints on…

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

Precise measurement of the angular deviation of an object is a common task in science and technology. Many methods use light for this purpose. Some of these exploit interference effects to achieve technological advantages, such as…

Quantum Physics · Physics 2020-08-19 G. H. Aguilar , R. S. Piera , P. L. Saldanha , R. L. de Matos Filho , S. P. Walborn

Long-baseline interferometry at optical and near-infrared wavelengths is an emerging technology which is quickly becoming a useful tool to investigate stellar atmospheres and to compare observations with models. Stellar atmosphere models…

Astrophysics · Physics 2007-05-23 Markus Wittkowski

Infrared space interferometers can surpass the spatial resolution limitations of single-dish space telescopes. However, stellar interferometers from space have not been realized because of technical difficulties. Two beams coming from…

Instrumentation and Methods for Astrophysics · Physics 2022-01-20 Taro Matsuo , Satoshi Ikari , Hirotaka Kondo , Sho Ishiwata , Shinichi Nakasuka , Tomoyasu Yamamuro

We present a feasibility study exploring the implementation of optical interferometry and speckle techniques with the 1.3-m Devasthal Fast Optical Telescope (DFOT) at ARIES, which is currently dedicated to photometric observations. Using…

Instrumentation and Methods for Astrophysics · Physics 2026-02-16 Km Nitu Rai , Arjun Dawn , Neelam Panwar , Jeewan C Pandey , Subrata Sarangi , Prasenjit Saha

Spectrograph is an optical device that is used to disperse photons of different energies $E$ into distinct directions and space locations, and to take a snapshot of the whole spectrum of photon energies with a spatially sensitive photon…

Optics · Physics 2015-06-03 Yuri Shvyd'ko

The Fraunhofer diffraction intensity distribution of Laguerre-Gaussian beam is studied in an angular-double-slit interferometer. We demonstrate that the spiral phase structure of vortex light can be clearly revealed in this interference…

Optics · Physics 2013-10-28 Ruifeng Liu , Junling Long , Feiran Wang , Yunlong Wang , Pei Zhang , Hong Gao , Fuli Li

We demonstrate a new scheme of infrared spectroscopy with visible light sources and detectors. The technique relies on the nonlinear interference of correlated photons, produced via spontaneous parametric down conversion in a nonlinear…