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In this paper it is developed a simple, analytical and very efficient method capable to provide control of optical beam's intensity over an arbitrary curvilinear (planar) trajectory. The same method also provides the possibility of managing…

Optics · Physics 2018-08-14 Michel Zamboni-Rached

We outline here a simple yet efficient method for finding optimized configurations of the elements of radio-astronomical interferometers with fixed pad locations. The method can be successfully applied, as we demonstrate, to define new…

Astrophysics · Physics 2009-11-11 A. Karastergiou , R. Neri , M. A. Gurwell

Light beams carrying orbital angular momentum are key resources in modern photonics. In many applications, the ability of measuring the complex spectrum of structured light beams in terms of these fundamental modes is crucial. Here we…

With the present and soon-to-be breakthrough of optical interferometry, countless objects shall be within reach of interferometers; yet, most of them are expected to remain only marginally resolved with hectometric baselines. In this paper,…

Astrophysics · Physics 2009-11-07 Regis Lachaume

Using kilometric arrays of air Cherenkov telescopes, intensity interferometry may increase the spatial resolution in optical astronomy by an order of magnitude, enabling images of rapidly rotating stars with structures in their…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Dainis Dravins , Stephan LeBohec , Hannes Jensen , Paul D. Nuñez

Within the last 10 years, long-baseline optical interferometry (LBOI) has benefited significantly from increased sensitivity, spatial resolution, and spectral resolution, e.g., measuring the diameters and asymmetries of single stars,…

High precision astrometry aims at source position determination to a very small fraction of the diffraction image size, in high SNR regime. One of the key limitations to such goal is the optical response variation of the telescope over a…

Instrumentation and Methods for Astrophysics · Physics 2021-04-08 Alberto Riva , Mario Gai , Alberto Vecchiato , Deborah Busonero , Mario G. Lattanzi , Federico Landini , Zhaoxiang Qi , Zhenghong Tang

Generating images from very long baseline interferometric observations poses a difficult, and generally not unique, inversion problem. This problem is simplified by the introduction of constraints, some generic (e.g., positivity of the…

Instrumentation and Methods for Astrophysics · Physics 2022-08-22 Avery E. Broderick , Dominic W. Pesce , Paul Tiede , Hung-Yi Pu , Roman Gold

Pupil mapping is a promising and unconventional new method for high contrast imaging being considered for terrestrial exoplanet searches. It employs two (or more) specially designed aspheric mirrors to create a high-contrast amplitude…

Astrophysics · Physics 2007-05-23 Ruslan Belikov , N. Jeremy Kasdin , Robert J. Vanderbei

Optical long baseline interferometry was recently established as a technique capable of resolving stars and their circumstellar environments at the milliarcsecond (mas) resolution level. This high-resolution opens an entire new window to…

Solar and Stellar Astrophysics · Physics 2018-08-28 Daniel Moser Faes

Intensity interferometry (II) exploits the second-order correlation to acquire the spatial frequency information of an object, which has been used to observe distant stars since 1950s. However, due to unreliability of employed imaging…

Image and Video Processing · Electrical Eng. & Systems 2017-12-08 Wentao Wang , Qi Han , Hui Chen , Yuan Yuan , Zhuo Xu

Image plane beam combination in optical interferometers multiplexes the interference fringes from multiple baselines onto a single detector. The beams of starlight are arranged in a non-redundant pattern at the entrance of the combiner so…

Instrumentation and Methods for Astrophysics · Physics 2022-02-16 Daniel J. Mortimer , David F. Buscher

After several generations of interferometers in radioastronomy, wide-field imaging at high angular resolution is today a major goal for trying to match optical wide-field performances. All the radio-interferometric, wide-field imaging…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 Jérôme Pety , Nemesio J. Rodriguez-Fernandez

The basic effect of the earth's atmospheric refraction on telescope operation is the reduction of the true zenith angle to the apparent zenith angle, associated with prismatic aberrations due to the dispersion in air. If one attempts…

Astrophysics · Physics 2007-05-23 Richard J. Mathar

We present 36 observations of 17 visual binaries of moderate separation (range from 0.15'' to 0.79'') made with the 50 cm Cassegrain telescope of the Jagiellonian University in Cracow. The speckle interferometry technique was combined with…

Astrophysics · Physics 2009-11-11 Artur Rutkowski , Waclaw Waniak

In a previous paper we described a method of estimating the single-measurement bias to be expected in astrometric observations of targets in crowded fields with the future Space Interferometry Mission (SIM). That study was based on a…

Astrophysics · Physics 2009-11-13 R. Sridharan , Ronald J. Allen

A new generation of telescopes with mirror diameters of 20 m or more, called extremely large telescopes (ELTs) has the potential to provide unprecedented imaging and spectroscopy of exo-planetary systems, if the difficulties in achieving…

Instrumentation and Methods for Astrophysics · Physics 2016-04-20 Richard A. Frazin

We propose a new, efficient multi-scale method to decompose a map (or signal in general) into components maps that contain structures of different sizes. In the widely-used wave transform, artifacts containing negative values arise around…

Instrumentation and Methods for Astrophysics · Physics 2022-04-11 Guang-Xing Li

Cubesats present unique opportunities for observational astronomy in the modern era. They are useful in observing difficult-to-access wavelength regions and long-term monitoring of interesting astronomical sources. However, conventional…

Instrumentation and Methods for Astrophysics · Physics 2025-07-14 Anwesh Kumar Mishra , Gourav Banerjee , Rekhesh Mohan , Maheswar Gopinathan

Recent advances in the area of plane segmentation from single RGB images show strong accuracy improvements and now allow a reliable segmentation of indoor scenes into planes. Nonetheless, fine-grained details of these segmentation masks are…

Computer Vision and Pattern Recognition · Computer Science 2020-03-31 Alexander Naumann , Laura Dörr , Niels Ole Salscheider , Kai Furmans
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