English
Related papers

Related papers: Spherical Trigonometry of the Projected Baseline A…

200 papers

In this paper, orthogonal projection along a geodesic to the chosen k-plane is introduced using edge and Gram matrix of an n-simplex in hyperbolic or spherical n-space. The distance from a point to k-plane is obtained by the orthogonal…

Metric Geometry · Mathematics 2014-12-24 Baki Karliga , Murat Savas , Atakan T. Yakut

Optical interferometry provides us with a unique opportunity to improve our understanding of stellar structure and evolution. Through direct observation of rotationally distorted photospheres at sub-milliarcsecond scales, we are now able to…

Solar and Stellar Astrophysics · Physics 2012-04-13 Gerard T. van Belle

Finding a suitable very long baseline (VLBI) interferometer geometry is a key task in planning observations, especially imaging sessions. The main characteristic of the quality of VLBI imaging data is the (u, v)-coverage. In the case when…

Instrumentation and Methods for Astrophysics · Physics 2024-04-01 I. I. Bulygin , M. A. Shchurov , A. G. Rudnitskiy

We study the formation of images in a reflective sphere in three configurations using caustics of the field of light rays. The optical wavefront emerging from a source point reaching a subject following passage through the optical system…

Interferometry is one of the central organizing principles of optics. Key to interferometry is the concept of optical delay, which facilitates spectral analysis in terms of time-harmonics. In contrast, when analyzing a beam in a Hilbert…

In this work we present an observational technique and a detailed analysis of the stellar interferograms produced by three bright stars: Betelgeuse, Rigel and Sirius. It is shown that the atmospheric turbulence is responsible for the…

Instrumentation and Methods for Astrophysics · Physics 2024-06-13 P. Rodriguez-Ovalle , A. Mendi-Martos , A . Angulo-Manzanas , I. Reyes-Rodriguez , M. Perez-Arrieta , M. A. Illarramendi , A. Sanchez-Lavega

We show that distances of objects at cosmological distances can be measured directly using interferometry. Our approach to interferometric parallax comes from analysis of 4-point amplitude and intensity correlations that can be generated…

Astrophysics · Physics 2008-11-26 Pankaj Jain , John P. Ralston

Modern dual-polarization receivers allow a radio telescope to characterize the full polarization state of incoming insterstellar radio waves. Many astronomers incorrectly consider a polarimeter to be the "backend" of the telescope. We go to…

Instrumentation and Methods for Astrophysics · Physics 2021-10-13 Timothy Robishaw , Carl Heiles

This paper is concerned with the use of the stereographic projection to map the points of a design on the sphere in three dimensions onto a two-dimensional stereogram. Details of the projection and its attendant stereogram are given and the…

Applications · Statistics 2024-07-08 Linda M. Haines

Interferometric particle imaging is a widely used optical measuring technique for the sizing of poly-dispersed spherical particles like droplets and bubbles. In its conventional approach, the method is limited to forward-scattering angles…

Fluid Dynamics · Physics 2023-03-29 Christian Sax , Maximilian Dreisbach , Jochen Kriegseis

This paper deals with the theoretical principle and optical design of a phase-shifting telescope-interferometer. What is called a "Telescope-Interferometer" (T-I) is indeed a novel, recently proposed Wavefront Error (WFE) sensing technique,…

Optics · Physics 2011-05-19 Francois Henault

We investigate interferometric techniques to estimate the deflection angle of an optical beam and compare them to the direct detection of the beam deflection. We show that quantum metrology methods lead to a unifying treatment for both…

Quantum Physics · Physics 2020-08-12 S. P. Walborn , G. H. Aguilar , P. L. Saldanha , L. Davidovich , R. L. de Matos Filho

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

This paper is the third part of a trilogy dealing with the principles, performance and limitations of what I named "Telescope-Interferometers" (TIs). The basic idea consists in transforming one telescope into a Wavefront Error (WFE) sensing…

Optics · Physics 2011-05-17 Francois Henault

In the paper, some geometric properties of the plane interception curve defined by a nonlinear ordinary differential equation are discussed. Its parametric representation is used to find the limits of some triangle elements associated with…

Differential Geometry · Mathematics 2023-07-25 Yagub N. Aliyev

What is long-baseline optical/IR stellar interferometry? A few years ago, many astronomers might not have been able to answer that question properly. This is today hopefully not the case anymore, because mainstream facilities, such as the…

Instrumentation and Methods for Astrophysics · Physics 2016-11-26 Florentin Millour

Polarimetric interferometry is a method allowing the study of the distribution of polarized flux at diffraction-limited resolution. Its basic observable is the ratio $\mathcal{R}$ of the visibilities of the object in two orthogonal…

Instrumentation and Methods for Astrophysics · Physics 2019-02-27 Boris Safonov , Pavel Lysenko , Maria Goliguzova , Dmitry Cheryasov

A geometric visualization is presented for the Brewster angle for a plane wave reflecting from an interface. The surface is assumed isotropic but it is allowed to display both dielectric and magnetic susceptibility, and hence the Brewster…

Popular Physics · Physics 2009-11-11 Ari Sihvola

A light ray in space is characterized by two vectors: (i) a transverse spatial-vector associated with the point where the ray intersects a given spherical cap; (ii) an angular-frequency vector which defines the ray direction of propagation.…

Optics · Physics 2023-04-10 Éric Fogret , Pierre Pellat-Finet

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