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Related papers: Optical configuration and analysis of the AMBER/VL…

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AIMS: We have found that the interferometric visibilities of VLTI-AMBER observations, extracted via the standard reduction package, are significantly biased when faint targets are concerned. The visibility biases derive from a time variable…

Astrophysics · Physics 2009-11-13 G. Li Causi , S. Antoniucci , E. Tatulli

The rapidly rotating primary component of Regulus A system has been observed, for the first time, using the technique of differential interferometry at high spectral resolution. The observations have been performed across the Br$_\gamma$…

Solar and Stellar Astrophysics · Physics 2017-12-12 S. Jankov , M. Hadjara , R. G. Petrov , P. Cruzalèbes , A. Spang , S. Lagarde

Aims. We study the enigmatic B[e] star MWC 300 to investigate its disk and binary with milli-arcsecond-scale angular resolution. Methods. We observed MWC 300 with the VLTI/AMBER instrument in the H and K bands and compared these…

With the widespread adoption of millimeter-wave (mmWave) massive multi-input-multi-output (MIMO) in vehicular networks, accurate beam prediction and alignment have become critical for high-speed data transmission and reliable access. While…

Information Theory · Computer Science 2026-03-27 Chenyiming Wen , Binpu Shi , Min Li , Ming-Min Zhao , Min-Jian Zhao , Jiangzhou Wang

We study the Be star $\delta$ Cen circumstellar disk using long-baseline interferometry which is the only observing technique capable of resolving spatially and spectroscopically objects smaller than 5 mas in the H and K b and. We used the…

We discuss the present performance and the future perspectives of VLBI in the 3 mm to 0.85 mm observing bands (so called mm-VLBI). The availability of new telescopes and the recent technical development towards larger observing bandwidth…

Astrophysics · Physics 2008-12-23 T. P. Krichbaum , U. Bach , D. A. Graham , W. Alef , A. Roy , A. Witzel , J. A. Zensus , M. Bremer , S. Sanchez

We present a compact setup based on a three-dimensional integrated optical component, allowing the mea- surement of spectrally resolved complex-visibilities for three channels of polychromatic light. We have tested a prototype of the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 Stefano Minardi , Allar Saviauk , Felix Dreisow , Stefan Nolte , Thomas Pertsch

We present the optical and cryo-mechanical solutions for the Spectrograph of VSI (VLTI Spectro-Imager), the second generation near-infrared (J, H and K bands) interferometric instrument for the VLTI. The peculiarity of this spectrograph is…

Astrophysics · Physics 2009-11-13 D. Lorenzetti , G. Li Causi , R. Speziali , F. Vitali , D. Loreggia , C. Baffa , P. Kern , L. Jocou , F. Malbet , P. Rabou

State-of-the art neutron spectrometers enable simultaneous measurements of high-dimensional datasets, allowing for a large collection rate of dynamic material properties. In this paper, we present the Algorithm for Multiplexing spectrometer…

Instrumentation and Detectors · Physics 2026-03-02 Jakob Lass , Victor Cohen , Benjamín Béjar Haro , Daniel G. Mazzone

We experimentally demonstrate the power scaling of optical vortices by the coherent beam combining, encompassing topological charges ranging from l=1 to l=5 realized on the basis of a Yb-doped fiber short-pulsed laser system. The combining…

Optics · Physics 2023-12-18 Hossein Fathi , Mikko Narhi , Regina Gumenyuk

We present recent studies using the near-infrared instrument AMBER of the VLT Interferometer (VLTI) to investigate the structure and shaping processes within the extended atmosphere of AGB stars. Spectrally resolved near-infrared AMBER…

Solar and Stellar Astrophysics · Physics 2011-05-18 M. Wittkowski , D. A. Boboltz , I. Karovicova , K. Ohnaka , A. E. Ruiz-Velasco , M. Scholz , A. Zijlstra

Since April 2011, realtime fringe tracking data are recorded simultaneously with data from the VLTI/AMBER interferometric beam combiner. Not only this offers possibilities to post-process AMBER reduced data to obtain more accurate…

Instrumentation and Methods for Astrophysics · Physics 2015-06-12 A. Merand , F. Patru , J. -P. Berger , I. Percheron , S. Poupar

The VLTI instrument GRAVITY combines the beams from four telescopes and provides phase-referenced imaging as well as precision-astrometry of order 10 microarcseconds by observing two celestial objects in dual-field mode. Their angular…

Structured light beams, such as optical vortices carrying orbital angular momentum, are essential for applications ranging from low-power optical communications to high-intensity laser-matter interactions. However, scaling their power and…

Optics · Physics 2025-12-29 Hossein Fathi , Rafael F. Barros , Regina Gumenyuk

We report the experimental realisation of a multibeam atom laser. A single continuous atom laser is outcoupled from a Bose-Einstein condensate (BEC) via an optical Raman transition. The atom laser is subsequently split into up to five…

Other Condensed Matter · Physics 2009-11-13 J. Dugué , G. Dennis , M. Jeppesen , M. T. Johnsson , C. Figl , N. P. Robins , J. D. Close

We propose a new instrumental concept for long-baseline optical single-mode interferometry using integrated optics which were developed for telecommunication. Visible and infrared multi-aperture interferometry requires many optical…

Astrophysics · Physics 2009-10-31 F. Malbet , P. Kern , I. Schanen-Duport , J. -P. Berger , K. Rousselet-Perraut

We present in this paper the design and characterisation of a new sub-system of the VLTI 2nd generation instrument GRAVITY: the Calibration Unit. The Calibration Unit provides all functions to test and calibrate the beam combiner…

Interferometric observations with three telescopes or more provide two observables: closure phase information together with visibilities measurements. When using single-mode interferometers, both observables have to be redefined in the…

Astrophysics · Physics 2009-11-11 E. Tatulli , A. Chelli

Integrated-optic, astronomical, two-beam and three-beam, interferometric combiners have been designed and fabricated for operation in the L band (3 - 4 microns) for the first time. The devices have been realized in titanium-indiffused,…

Instrumentation and Methods for Astrophysics · Physics 2018-05-23 Hsien-kai Hsiao , K. A. Winick , John D. Monnier , Jean-Philippe Berger

A novel concept for coherent beam combining is presented based on a simple setup with microlens arrays. These standard components are used in a proof-of-principle experiment for both coherent beam splitting and combination of 5 x 5 beams.…