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Related papers: Tropospheric Phase Calibration in Millimeter Inter…

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In radio astronomy, accurate calibration is of crucial importance for the new generation of radio interferometers. More specifically, because of the potential presence of outliers which affect the measured data, robustness needs to be…

Instrumentation and Methods for Astrophysics · Physics 2018-08-01 Virginie Ollier , Mohammed Nabil El Korso , André Ferrari , Rémy Boyer , Pascal Larzabal

During the last years the transfer of frequency signals through optical fibers has shown ultra low instabilities in various configurations. The outstanding experimental results of such point-to-point connections is motivation to develop a…

Optics · Physics 2019-10-25 M. Rost , M. Fujieda , D. Piester

Coherent measurement of quantum signals used for continuous-variable (CV) quantum key distribution (QKD) across satellite-to-ground channels requires compensation of phase wavefront distortions caused by atmospheric turbulence. One…

Quantum Physics · Physics 2025-08-13 Nathan K. Long , Robert Malaney , Kenneth J. Grant

This paper presents a polarization calibration method applied to a microwave polarimeter demonstrator based on a near-infrared (NIR) frequency up-conversion stage that allows both optical correlation and signal detection at a wavelength of…

Instrumentation and Methods for Astrophysics · Physics 2022-10-25 Francisco J. Casas , Patricio Vielva , R. Belen Barreiro , Enrique Martínez-González , G. Pascual-Cisneros

Several experimental results show that it is possible to extract useful phase information from reflected GPS signals over the oceans. In this work we begin the development of the theoretical background to account for these results and fully…

Atmospheric and Oceanic Physics · Physics 2007-05-23 Giulio Ruffini i Fores , Francois Soulat

Our ability to calibrate current kilometer-scale interferometers can potentially confound the inference of astrophysical signals. Current calibration uncertainties are well described by a Gaussian process. I exploit this description to…

Instrumentation and Methods for Astrophysics · Physics 2022-04-27 Reed Essick

An interferometric method is implemented in order to accurately assess the thermal fluctuations of a micro-cantilever sensor in liquid environments. The power spectrum density (PSD) of thermal fluctuations together with Sader's model of the…

Soft Condensed Matter · Physics 2015-11-11 Felipe Aguilar Sandoval , Manuel Sepúlveda , Ludovic Bellon , Francisco Melo

Calibration of the Advanced LIGO detectors is the quantification of the detectors' response to gravitational waves. Gravitational waves incident on the detectors cause phase shifts in the interferometer laser light which are read out as…

This study illustrates the application of a random strong line (RSL) model of radiative transfer to the interpretation of satellite observations of the upwelling radiation in the 6.3 micron water vapor absorption band. The model, based upon…

ao-sci · Physics 2008-02-03 Brian J. Soden , Francis P. Bretherton

Time-variable absorption by water vapor in Earth's atmosphere presents an important source of systematic error for a wide range of ground-based astronomical measurements, particularly at near-infrared wavelengths. We present results from…

Instrumentation and Methods for Astrophysics · Physics 2017-12-20 Dan Li , Cullen H. Blake , David Nidever , Samuel Halverson

Signals from radio pulsars show a wavelength-dependent delay due to dispersion in the interstellar plasma. At a typical observing wavelength, this delay can vary by tens of microseconds on five-year time scales, far in excess of signals of…

The sky-averaged, or global, background of redshifted $21$ cm radiation is expected to be a rich source of information on cosmological reheating and reionizaton. However, measuring the signal is technically challenging: one must extract a…

Instrumentation and Methods for Astrophysics · Physics 2016-08-03 Tejaswi Venumadhav , Tzu-Ching Chang , Olivier Doré , Christopher M. Hirata

In order to reach the sensitivity required to detect gravitational waves, pulsar timing array experiments need to mitigate as much noise as possible in timing data. A dominant amount of noise is likely due to variations in the dispersion…

Instrumentation and Methods for Astrophysics · Physics 2015-06-19 K. J. Lee , C. G. Bassa , G. H. Janssen , R. Karuppusamy , M. Kramer , K. Liu , D. Perrodin , R. Smits , B. W. Stappers , R. van Haasteren , L. Lentati

Observation of multifrequency angular power spectrum of the redshifted 21-cm brightness temperature fluctuation from the neutral hydrogen holds the key to understand the structure formation and its evolution during the reionization and…

Cosmology and Nongalactic Astrophysics · Physics 2025-05-28 Saikat Gayen , Jais Kumar , Prasun Dutta , Khandakar Md Asif Elahi , Samir Choudhuri , Nirupam Roy

Traditional color and airmass corrections can typically achieve ~0.02 mag precision in photometric observing conditions. A major limiting factor is the variability in atmospheric throughput, which changes on timescales of less than a night.…

Instrumentation and Methods for Astrophysics · Physics 2013-02-26 Ting Li , D. L. DePoy , R. Kessler , D. L. Burke , J. L. Marshall , J. Wise , J. -P. Rheault , D. W. Carona , S. Boada , T. Prochaska , R. Allen

A Low Humidity and Temperature Profiling (LHATPRO) microwave radiometer, manufactured by Radiometer Physics GmbH (RPG), is used to monitor sky conditions over ESO's Paranal observatory in support of VLT science operations. The unit measures…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Richard R. Querel , Florian Kerber

The residual gain errors add to the systematics of the radio interferometric observations. In case of the high dynamic range observations, these systematic effects dominates over the thermal noise of the observation. In this work, we…

Instrumentation and Methods for Astrophysics · Physics 2021-01-13 Jais Kumar , Prasun Dutta , Nirupam Roy

We report a new experimental approach for observing mesoscopic fluctuations underlying the thermodynamic anomalies of ambient liquid water. In this approach, two sound velocity measurements with different frequencies, namely inelastic X-ray…

Calibration is crucial for ensuring the performance of phased array since amplitude-phase imbalance between elements results in significant performance degradation. While amplitude-only calibration methods offer advantages when phase…

Signal Processing · Electrical Eng. & Systems 2025-04-24 Shiyuan Li , Yuyue Zhou , Chi Zhang , Liang Kong , Kebin Liu , Yihan Xie , Chong He

Using kilometric arrays of air Cherenkov telescopes, intensity interferometry may increase the spatial resolution in optical astronomy by an order of magnitude, enabling images of rapidly rotating stars with structures in their…

Instrumentation and Methods for Astrophysics · Physics 2015-06-05 Dainis Dravins , Stephan LeBohec , Hannes Jensen , Paul D. Nuñez
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