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Adaptive measurements were recently shown to significantly improve the performance of quantum state tomography. Utilizing information about the system for the on-line choice of optimal measurements allows to reach the ultimate bounds of…

A major stage of radio interferometric data processing is calibration or the estimation of systematic errors in the data and the correction for such errors. A stochastic error (noise) model is assumed, and in most cases, this underlying…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 S. Kazemi , S. Yatawatta

The ionosphere introduces chromatic distortions on low frequency radio waves, and thus poses a hurdle for 21-cm cosmology. In this paper we introduce time-varying chromatic ionospheric effects on simulated antenna temperature data of a…

Instrumentation and Methods for Astrophysics · Physics 2022-07-20 Emma Shen , Dominic Anstey , Eloy de Lera Acedo , Anastasia Fialkov

Direction dependent calibration of widefield radio interferometers estimates the systematic errors along multiple directions in the sky. This is necessary because with most systematic errors that are caused by effects such as the ionosphere…

Instrumentation and Methods for Astrophysics · Physics 2021-12-22 Sarod Yatawatta

Context: Radio interferometers measure frequency components of the sky brightness, modulated by the gains of the individual radio antennas. Due to atmospheric turbulence and variations in the operational conditions of the antennas these…

Instrumentation and Methods for Astrophysics · Physics 2023-10-25 Jakob Roth , Philipp Arras , Martin Reinecke , Richard A. Perley , Rüdiger Westermann , Torsten A. Enßlin

We present an efficient method for evaluating random phase errors in phase shifters within photonic integrated circuits, avoiding the computational cost of traditional Monte Carlo simulations. By modeling spatially correlated manufacturing…

Optics · Physics 2025-04-09 Zijian Zhang

In this study, we introduce a novel analytical Gaussian Process (GP) cosmography methodology, leveraging the differentiable properties of GPs to derive key cosmological quantities analytically. Our approach combines cosmic chronometer (CC)…

Cosmology and Nongalactic Astrophysics · Physics 2024-04-19 Bikash R. Dinda

With ever increasing data rates produced by modern radio telescopes like LOFAR and future telescopes like the SKA, many data processing steps are overwhelmed by the amount of data that needs to be handled using limited compute resources.…

Instrumentation and Methods for Astrophysics · Physics 2020-03-18 Sarod Yatawatta

In preparation for the era of the time-domain astronomy with upcoming large-scale surveys, we propose a state-space representation of a multivariate damped random walk process as a tool to analyze irregularly-spaced multi-filter light…

Instrumentation and Methods for Astrophysics · Physics 2020-11-19 Zhirui Hu , Hyungsuk Tak

Radio astronomical imaging using aperture synthesis telescopes requires deconvolution of the point spread function as well as calibration of the instrumental characteristics (primary beam) and foreground (ionospheric/atmospheric) effects.…

Instrumentation and Methods for Astrophysics · Physics 2011-11-24 Juan M. Uson , William D. Cotton

Likelihood fitting to two-point clustering statistics made from galaxy surveys usually assumes a multivariate normal distribution for the measurements, with justification based on the central limit theorem given the large number of…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-23 Mike Shengbo Wang , Will J. Percival , Santiago Avila , Robert Crittenden , Davide Bianchi

Interferometric scattering microscopy (iSCAT) can image the dynamics of nanometer-scale systems. The typical approach to analyzing interferometric images involves intensive processing, which discards data and limits the precision of…

Precise measurements in optical and atomic systems often rely on differential interferometry. This method allows to handle large and correlated phase noise contributions -- such as environmental vibrations, thermal fluctuations, or…

Quantum Physics · Physics 2025-03-25 Luca Pezzè , Andrea Santoni , Chiara Mazzinghi , Marco Fattori , Augusto Smerzi

The calibration of modern radio interferometers is a significant challenge, specifically at low frequencies. In this perspective, we propose a novel iterative calibration algorithm, which employs the popular sparse representation framework,…

Instrumentation and Methods for Astrophysics · Physics 2016-06-06 Martin Brossard , Mohamed Nabil El Korso , Marius Pesavento , Rémy Boyer , Pascal Larzabal

Calibration is an essential step in radio interferometric data processing that corrects the data for systematic errors and in addition, subtracts bright foreground interference to reveal weak signals hidden in the residual. These weak and…

Instrumentation and Methods for Astrophysics · Physics 2019-05-08 Sarod Yatawatta

(Sub-)millimetre single-dish telescopes feature faster mapping speeds and access larger spatial scales than their interferometric counterparts. However, atmospheric fluctuations tend to dominate their signals and complicate recovery of the…

Instrumentation and Methods for Astrophysics · Physics 2026-03-30 Jonas Würzinger , Joshiwa van Marrewijk , Thomas W. Morris , Richard Fuchs , Tony Mroczkowski , Lukas Heinrich

Gaussian process regression is widely used because of its ability to provide well-calibrated uncertainty estimates and handle small or sparse datasets. However, it struggles with high-dimensional data. One possible way to scale this…

Machine Learning · Statistics 2024-02-02 Bernardo Fichera , Viacheslav Borovitskiy , Andreas Krause , Aude Billard

Radio interferometric gain calibration can be biased by incomplete sky models and radio frequency interference, resulting in calibration artefacts that can restrict the dynamic range of the resulting images. It has been suggested that…

Instrumentation and Methods for Astrophysics · Physics 2019-10-21 Ulrich Armel Mbou Sob , Hertzog Landman Bester , Oleg Smirnov , Jonathan Kenyon , Trienko Grobler

This paper presents a new Bayesian model and algorithm used for depth and intensity profiling using full waveforms from the time-correlated single photon counting (TCSPC) measurement in the limit of very low photon counts. The model…

Applications · Statistics 2016-04-20 Yoann Altmann , Ximing Ren , Aongus McCarthy , Gerald S. Buller , Steve McLaughlin

Recently, a novel linear model predictive control algorithm based on a physics-informed Gaussian Process has been introduced, whose realizations strictly follow a system of underlying linear ordinary differential equations with constant…

Optimization and Control · Mathematics 2025-05-01 Adrian Lepp , Jörn Tebbe , Andreas Besginow