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Related papers: AMBER closure and differential phases: accuracy an…

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We describe a new method which achieves high precision Very Long Baseline Interferometry (VLBI) astrometry in observations at millimeter wavelengths. It combines fast frequency-switching observations, to correct for the dominant…

Instrumentation and Methods for Astrophysics · Physics 2015-05-27 Maria J. Rioja , Richard Dodson

The fusion of LiDARs and cameras has been increasingly adopted in autonomous driving for perception tasks. The performance of such fusion-based algorithms largely depends on the accuracy of sensor calibration, which is challenging due to…

Computer Vision and Pattern Recognition · Computer Science 2024-03-19 Yuxuan Xiao , Yao Li , Chengzhen Meng , Xingchen Li , Jianmin Ji , Yanyong Zhang

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

The calibration and analysis of polarization observations in Very Long Baseline Interferometry (VLBI) requires the use of specific algorithms that suffer from several limitations, closely related to assumptions in the data properties that…

Instrumentation and Methods for Astrophysics · Physics 2021-02-10 Ivan Marti-Vidal , Alejandro Mus , Michael Janssen , Pablo de Vicente , Javier Gonzalez

Accurate phase estimation plays a pivotal role in quantum metrology, yet its precision is significantly affected by noise, particularly phase-diffusive noise caused by phase drift. To address this challenge, the joint estimation of phase…

Quantum Physics · Physics 2026-03-17 Ben Wang , Minghao Mi , Huangqiuchen Wang , Qian Xie , Lijian Zhang

Many advanced techniques have been developed, tested and implemented in the last decades in almost all circular accelerators across the world to measure the linear optics. However, the greater availability and accuracy of beam diagnostics…

Accelerator Physics · Physics 2018-04-18 Andrea Franchi

Very long baseline interferometry (VLBI) provides the resolution needed to make precision measurements of a pulsar's parallax and proper motion. In making these measurements, the astronomer is faced with difficult calibration problems and a…

Astrophysics · Physics 2007-05-23 Walter Brisken

The present paper investigates and discusses the ability of the Hartmann test with 4-aperture DIMM to measure the atmospheric primary aberrations which, in turn, can be used for calculation of the atmospheric coherence time. Through…

Instrumentation and Methods for Astrophysics · Physics 2011-03-09 Ramin Shomali , Sadollah Nasiri , Ahmad Darudi

In this article, we present a deflection measurement setup for Atomic Force Microscopy (AFM). It is based on a quadrature phase differential interferometer: we measure the optical path difference between a laser beam reflecting above the…

Instrumentation and Detectors · Physics 2015-06-16 Pierdomenico Paolino , Felipe A. Aguilar Sandoval , Ludovic Bellon

Unitary Fourier transform lies at the core of the multitudinous computational and metrological algorithms. Here we show experimentally how the unitary Fourier transform-based phase estimation protocol, used namely in quantum metrology, can…

Our motion relative to the cosmic-microwave-background (CMB) rest frame deflects light rays giving rise to shifts as large as L -> L(1+beta), where beta=0.00123 is our velocity (in units of the speed of light) on measurements CMB…

Cosmology and Nongalactic Astrophysics · Physics 2014-01-22 Donghui Jeong , Jens Chluba , Liang Dai , Marc Kamionkowski , Xin Wang

Beamforming techniques utilized either at the transmitter or the receiver terminals have achieved superior quality-of-service performances from both the multi-antenna wireless communications systems, communications intelligence and radar…

Signal Processing · Electrical Eng. & Systems 2023-06-09 M. Yaser Yağan , Ahmet F. Coşkun , Ali E. Pusane

The advent of a new generation of low frequency interferometers has opened a direct window into the Epoch of Reionisation (EoR). However, key to a detection of the faint 21-cm signal, and reaching the sensitivity limits of these arrays, is…

Instrumentation and Methods for Astrophysics · Physics 2018-12-05 Ronniy C. Joseph , Cathryn M. Trott , Randall B. Wayth

Atmospheric propagation errors are a main constraint on the accuracy of Very Long Baseline Interferometry (VLBI) astrometry. For relative astrometry, differential techniques can mitigate these errors, but their effectiveness diminishes with…

Instrumentation and Methods for Astrophysics · Physics 2025-05-26 Jingdong Zhang , Bo Zhang , Shuangjing Xu , Maria J. Rioja , Richard Dodson , Xiaofeng Mai , Oleg Titov

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

Classically, optical and near-infrared interferometry have relied on closure phase techniques to produce images. Such techniques allow us to achieve modest dynamic ranges. In order to test the feasibility of next generation optical…

We use camera-in-the-loop calibration to calibrate a phase-only spatial light modulator (SLM) in a far-field hologram setup. The recorded intensity distributions achieve a high degree of consistency with the calculated results, indicating a…

Optics · Physics 2026-02-18 Markus Zimmermann , Andreas Brenner , Tobias Haist , Stephan Reichelt

This paper presents a novel calibration algorithm for Multi-Focus Plenoptic Cameras (MFPCs) using raw images only. The design of such cameras is usually complex and relies on precise placement of optic elements. Several calibration…

Image and Video Processing · Electrical Eng. & Systems 2021-11-10 Mathieu Labussière , Céline Teulière , Frédéric Bernardin , Omar Ait-Aider

The Mingantu Spectral Radioheliograph (MUSER), a new generation of solar dedicated radio imaging-spectroscopic telescope, has realized high-time, high-angular, and high-frequency resolution imaging of the sun over an ultra-broadband…

Instrumentation and Methods for Astrophysics · Physics 2022-10-17 Zhichao Zhou , Yihua Yan , Linjie Chen , Wei Wang , Suli Ma

In the aspect of longitudinal beam bunching, the bunching strength can be controlled by the RF cavity phase and voltage. However, these machine parameters are different from those that interact with the beam itself. In order to gain control…

Accelerator Physics · Physics 2023-06-16 K. Shih , I. Petrushina , V. N. Litvinenko , I. Pinayev , J. Ma , G. Wang , Y. Jing , Y. Wu