English
Related papers

Related papers: Atmosphere-Corrected Phase-Referencing

200 papers

Using a two-photon interference technique, we measure the delay for single-photon wavepackets to be transmitted through a multilayer dielectric mirror, which functions as a ``photonic bandgap'' medium. By varying the angle of incidence, we…

Quantum Physics · Physics 2016-09-08 Aephraim M. Steinberg , Raymond Y. Chiao

The recent development of $\theta\mhyphen\theta$ techniques in pulsar scintillometry has opened the door for new high resolution imaging techniques of the scattering medium. By solving the phase retrieval problem and recovering the…

Instrumentation and Methods for Astrophysics · Physics 2023-08-09 Daniel Baker , Walter Brisken , Marten H. van Kerkwijk , Rik van Lieshout , Ue-Li Pen

This report models the refractive index above a telescope site by an atmosphere with exponential decay of the refractive index (susceptibility) as a function of altitude. The air is represented as a spherical hull around the surface. We…

Instrumentation and Methods for Astrophysics · Physics 2020-08-18 Richard J. Mathar

One of the most ubiquitous techniques within attosecond science is the so-called Reconstruction of Attosecond Bursts by Interference of Two-Photon Transitions (RABBITT). Originally proposed for the characterization of attosecond pulses, it…

Very long baseline interferometry (VLBI) technique allows us to determine positions of thousands of radio sources using the absolute astrometry approach. I have investigated the impact of a selection of observing frequencies in a range from…

Instrumentation and Methods for Astrophysics · Physics 2024-05-14 Leonid Petrov

Strong lensing time-delay systems constrain cosmological parameters via the so-called time-delay distance and the angular diameter distance to the lens. In previous studies, only the former information was used. In this paper, we show that…

Cosmology and Nongalactic Astrophysics · Physics 2016-04-27 Inh Jee , Eiichiro Komatsu , Sherry H. Suyu , Dragan Huterer

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

Time delay estimation arises in many applications in which a multipath medium has to be identified from pulses transmitted through the channel. Various approaches have been proposed in the literature to identify time delays introduced by…

Information Theory · Computer Science 2011-01-05 Kfir Gedalyahu , Yonina C. Eldar

We report on the first wide-field, high-precision astrometric analysis of the 13 extragalactic radio sources of the complete S5 polar cap sample at 15.4 GHz. We describe new algorithms developed to enable the use of differenced phase delays…

Astrophysics · Physics 2009-11-13 I. Marti-Vidal , J. M. Marcaide , J. C. Guirado , M. A. Perez-Torres , E. Ros

A significant challenge in the study of transient astrophysical phenomena is the identification of bogus events, among which human-made satellites and debris in Earth orbit remain major contaminants. Existing pipelines effectively identify…

Instrumentation and Methods for Astrophysics · Physics 2025-05-14 J. P. Carvajal , F. E. Bauer , I. Reyes-Jainaga , F. Förster , A. M. Muñoz Arancibia , M. Catelan , P. Sánchez-Sáez , C. Ricci , A. Bayo

Dispersive delays due to the Solar wind introduce excess noise in high-precision pulsar timing experiments, and must be removed in order to achieve the accuracy needed to detect, e.g., low-frequency gravitational waves. In current pulsar…

Gravitational time delays, observed in strong lens systems where the variable background source is multiply-imaged by a massive galaxy in the foreground, provide direct measurements of cosmological distance that are very complementary to…

Cosmology and Nongalactic Astrophysics · Physics 2017-01-18 Tommaso Treu , Philip J. Marshall

Attosecond ionization time-delays at photoelectron energies above typically 10 eV are usually interpreted using the so called asymptotic approximation as a sum of the atomic or molecular delays with a universal laser-induced contribution.…

We have measured a time delay of 25.3 +/- 2.0 d (1-sigma confidence) in the Einstein ring gravitational lens system PKS 1830-211 from an analysis of archival VLA and ATCA monitoring data observed between 1997 and 2004. A small portion of…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-26 A. D. Biggs

We present in this paper accurate positions of 857 sources derived from the astrometric analysis of 16 eleven-hour experiments from the Very Long Baseline Array imaging and polarimetry survey at 5 GHz (VIPS). Among observed sources,…

Cosmology and Nongalactic Astrophysics · Physics 2011-11-22 Leonid Petrov , Gregory Taylor

In urban areas, the quality of global navigation satellite system (GNSS) signals deteriorates, leading to reduced positioning accuracy. To address this issue, 3D-mapping-aided (3DMA) techniques, such as shadow matching and zonotope shadow…

Signal Processing · Electrical Eng. & Systems 2025-02-18 Sanghyun Kim , Jiwon Seo

Given a set of astrometric observations of the same object, the problem of orbit determination is to compute the orbit and to assess its uncertainty and reliability. For the next generation surveys, with much larger number density of…

The Multipath effect in Time-of-Flight(ToF) cameras still remains to be a challenging problem that hinders further processing of 3D data information. Based on the evidence from previous literature, we explored the possibility of using…

Computer Vision and Pattern Recognition · Computer Science 2016-01-13 Mojmir Mutny , Rahul Nair , Jens-Malte Gottfried

Time-Delay Interferometry (TDI) is the data processing technique that cancels the large laser phase fluctuations affecting the one-way Doppler measurements made by unequal-arm space-based gravitational wave interferometers. By taking finite…

General Relativity and Quantum Cosmology · Physics 2022-05-11 Sanjeev Dhurandhar , Prasanna Joshi , Massimo Tinto

We report the results of a phase-referencing study aimed at uncovering precession of the VLBI jet of BL Lac. The observations were conducted at 8, 15, 22, and 43 GHz and consist of seven epochs spanning about two years. We investigated the…

Astrophysics · Physics 2007-11-26 A. Sokolov , T. Cawthorne
‹ Prev 1 3 4 5 6 7 10 Next ›