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In the context of adaptive optics for astronomy, one can rely on the statistics of the turbulent phase to assess a part of the system's performance. Temporal statistics with one source and spatial statistics with two sources are well-known…

Instrumentation and Methods for Astrophysics · Physics 2022-09-05 Cédric Plantet , Giulia Carlà , Guido Agapito , Lorenzo Busoni

The behavior of an adaptive optics (AO) system for ground-based high contrast imaging (HCI) dictates the achievable contrast of the instrument. In conditions where the coherence time of the atmosphere is short compared to the speed of the…

Instrumentation and Methods for Astrophysics · Physics 2022-05-31 Maaike A. M. van Kooten , Rebecca Jensen-Clem Sylvain Cetre , Sam Ragland , Charlotte Z. Bond , J. Fowler , Peter Wizinowich

For the submillimeter band observations, we have been routinely adopting the calibration cycle time of 20-30 minutes, which is the same as any typical centimeter and millimeter band observations. This cycle time, largely corrects only the…

Astrophysics · Physics 2007-06-04 Dharam Vir Lal , Satoki Matsushita , Jeremy Lim

We apply a pulsed-light interferometer to measure both the intensity and the phase of light that is transmitted through a strongly scattering disordered material. From a single set of measurements we obtain the time-resolved intensity,…

Disordered Systems and Neural Networks · Physics 2009-11-10 I. M. Vellekoop , P. Lodahl , A. Lagendijk

We present the details of predicting atmospheric turbulence by mining Zernike moment data obtained from simulations as well as experiments. Temporally correlated optical wave-fronts were simulated such that they followed Kolmogorov phase…

Instrumentation and Methods for Astrophysics · Physics 2011-09-14 Akondi Vyas , M. B. Roopashree , B. Raghavendra Prasad

Traditional time series forecasting methods optimize for accuracy alone. This objective neglects temporal consistency, in other words, how consistently a model predicts the same future event as the forecast origin changes. We introduce the…

Machine Learning · Computer Science 2026-04-24 Chutian Ma , Grigorii Pomazkin , Giacinto Paolo Saggese , Paul Smith

Residual speckles in adaptive optics (AO) images represent a well-known limitation on the achievement of the contrast needed for faint source detection. Speckles in AO imagery can be the result of either residual atmospheric aberrations,…

The advent of a new generation of Adaptive Optics systems called Wide Field AO (WFAO) mark the beginning of a new era. By using multiple Guide Stars (GSs), either Laser Guide Stars (LGSs) or Natural Guide Stars (NGSs), WFAO significantly…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Benoit Neichel , Elena Masciadri , Andrés R. Guesalaga , Franck Lascaux , Clémentine Béchet

Photometric calibration is currently the dominant source of systematic uncertainty in exploiting type Ia supernovae to determine the nature of the dark energy. We review our ongoing program to address this calibration challenge by…

Instrumentation and Methods for Astrophysics · Physics 2012-06-29 Christopher W. Stubbs , John L. Tonry

We study the potential of adaptive optics (AO) to protect entanglement of high-dimensional photonic orbital-angular-momentum (OAM) states against turbulence-induced phase distortions. We demonstrate that AO is able to reduce crosstalk among…

Optical signal propagation through underwater channels is affected by three main degrading phenomena, namely absorption, scattering, and fading. In this paper, we experimentally study the statistical distribution of intensity fluctuations…

We report a weighing metrology experiment of a single silica microsphere optically trapped and immersed in air. Based on fluctuations about thermal equilibrium, three different mass measurements are investigated, each arising from one of…

The response of the Advanced LIGO interferometers is known to vary with time [arXiv:1608.05134]. Accurate calibration of the interferometers must therefore track and compensate for temporal variations in calibration model parameters. These…

Instrumentation and Methods for Astrophysics · Physics 2023-01-11 Madeline Wade , Aaron D. Viets , Theresa Chmiel , Madeline Stover , Leslie Wade

The effects of sampling rate and total measurement time have been determined for single-point measurements of step fluctuations within the context of first-passage properties. Time dependent STM has been used to evaluate step fluctuations…

Statistical Mechanics · Physics 2007-05-23 D. B. Dougherty , C. Tao , O. Bondarchuk , W. G. Cullen , E. D. Williams , M. Constantin , C. Dasgupta , S. Das Sarma

We characterize the performance of a fixed grid of solar panels on the basis of data taken under clear sky conditions over 12 months. We confirm that the power output is linearly proportional to cos(theta), where theta is the angular…

Instrumentation and Methods for Astrophysics · Physics 2022-06-09 Kevin Krisciunas

The mesoscale model Meso-NH is used to simulate the optical turbulence at Mt Graham (Arizona, USA), site of the Large Binocular Telescope. Measurements of the CN2-profiles obtained with a generalized scidar from 41 nights are used to…

Instrumentation and Methods for Astrophysics · Physics 2011-05-16 S. Hagelin , E. Masciadri , F. Lascaux

In order to increase the corrected field of view of an adaptive optics (AO) system, several deformable mirrors (DM) have to be placed in the conjugate planes of the dominant turbulent layers (multi-conjugate adaptive optics, MCAO [Beckers…

Astrophysics · Physics 2022-04-20 T. Berkefeld , A. Glindemann , S. Hippler

Accurate flux density calibration is essential for precise analysis and interpretation of observations across different observation modes and instruments. In this research, we firstly introduce the flux calibration model incorporated in…

Instrumentation and Methods for Astrophysics · Physics 2024-09-04 Ziming Liu , Jie Wang , Yingjie Jing , Zhi-Yu Zhang , Chen Xu , Tiantian Liang , Qingze Chen , Ningyu Tang , Qingliang Yang

Adaptive optics (AO) systems deliver high-resolution images that may be ideal for precisely measuring positions of stars (i.e. astrometry) if the system has stable and well-calibrated geometric optical distortions. A calibration unit,…

Instrumentation and Methods for Astrophysics · Physics 2019-08-14 Maxwell Service , Jessica R. Lu , Mark Chun , Ryuiji Suzuki , Matthias Schoeck , Jenny Atwood , David Andersen , Glen Herriot

Scintillator detectors electronics is recalibrated against the datasheet given by the manufacturer. Optimal and mutual dependent values of (a) high voltage at PMT (Photomultiplier Tube), (b) amplifier gain, (c) average time to count the…

Instrumentation and Detectors · Physics 2023-03-07 Mayank Goswami , Kajal Kumari
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