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At sufficiently low frequencies, no ground-based radio array will be able to produce high resolution images while looking through the ionosphere. A space-based array will be needed to explore the objects and processes which dominate the sky…

We present a technique-led review of the progression of precise radio astrometry, from the first demonstrations, half a century ago, until to date and into the future. We cover the developments that have been fundamental to allow high…

Instrumentation and Methods for Astrophysics · Physics 2020-10-06 María Rioja , Richard Dodson

The NRAO Very Long Baseline Array (VLBA) was used at 1.4 GHz to image 20 compact sources in the inner 1-degree radius of the Spitzer VLA First-Look Survey. Twelve sources were detected with the VLBA, with peak flux densities above 2 mJy at…

Astrophysics · Physics 2009-11-10 J. M. Wrobel , M. A. Garrett , J. J. Condon , R. Morganti

The Earth's atmospheric turbulence degrades the precision of ground-based astrometry. Here, we discuss these limitations and propose that, with proper treatment of systematics and by leveraging the many epochs available from the Korean…

Phase estimation is the most investigated protocol in quantum metrology, but its performance is affected by the presence of noise, also in the form of imperfect state preparation. Here we discuss how to address this scenario by using a…

In this work, we derive a model for the covariance of the visual residuals in multi-view SfM, odometry and SLAM setups. The core of our approach is the formulation of the residual covariances as a combination of geometric and photometric…

Computer Vision and Pattern Recognition · Computer Science 2022-02-03 Alejandro Fontan , Laura Oliva , Javier Civera , Rudolph Triebel

Modern interferometric imaging relies on advanced calibration that incorporates direction-dependent effects. Their increasing number of antennas (e.g. in LOFAR, VLA, MeerKAT/SKA) and sensitivity are often tempered with the accuracy of their…

Instrumentation and Methods for Astrophysics · Physics 2019-03-20 K. Iheanetu , J. N. Girard , O. Smirnov , K. M. B. Asad , M. de Villiers , K. Thorat , S. Makhathini , R. A. Perley

This paper introduces the multiband periodogram, a general extension of the well-known Lomb-Scargle approach for detecting periodic signals in time-domain data. In addition to advantages of the Lomb-Scargle method such as treatment of…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 Jacob T. VanderPlas , Zeljko Ivezic

The large constellations of spacecraft planned for use in cislunar space (on the Lunar surface, in Lunar orbit, and in the vicinity of the Lunar Gateway) require new solutions for positioning, navigation and timing (PNT). Here, I describe…

Instrumentation and Methods for Astrophysics · Physics 2020-05-21 T. M. Eubanks

This paper proposes a fine-grained self-localization method for outdoor robotics that utilizes a flexible number of onboard cameras and readily accessible satellite images. The proposed method addresses limitations in existing cross-view…

Computer Vision and Pattern Recognition · Computer Science 2023-08-17 Shan Wang , Yanhao Zhang , Akhil Perincherry , Ankit Vora , Hongdong Li

This work aims to explore the possibilities of determining the long-period part of the precession-nutation of the Earth with techniques other than very long baseline interferometry (VLBI). Lunar laser ranging (LLR) is chosen for its…

Geophysics · Physics 2019-07-03 Yu-Ting Cheng , Jia-Cheng Liu , Zi Zhu

Cosmic Microwave Background (CMB) lensing is a powerful probe of the matter distribution in the Universe. The standard quadratic estimator, which is typically used to measure the lensing signal, is known to be suboptimal for low-noise…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-26 Benjamin Horowitz , Simone Ferraro , Blake D. Sherwin

The Low Frequency Array (LOFAR) is a new generation of electronic radio telescope based on aperture array technology. The telescope is being developed by ASTRON, and currently being rolled out across the Netherlands and other countries in…

Cosmology and Nongalactic Astrophysics · Physics 2009-03-07 M. A. Garrett , H. Rampadarath , E. Lenc , Olaf Wucknitz

In some scenarios, a single input image may not be enough to allow the object classification. In those cases, it is crucial to explore the complementary information extracted from images presenting the same object from multiple perspectives…

Computer Vision and Pattern Recognition · Computer Science 2022-05-24 Gabriel Machado , Keiller Nogueira , Matheus Barros Pereira , Jefersson Alex dos Santos

We propose to realize microwave quantum illumination in weak coupling regime based on multimode optomechanical systems. In our proposal the multimode together with a frequency-mismatch process could reduce mechanical thermal noise.…

Quantum Physics · Physics 2017-01-24 Wen-Juan Yang , Xiang-Bin Wang

Planetary ephemerides have been developed and improved over centuries. They are a fundamental tool for understanding solar system dynamics, and essential for planetary and small body mass determinations, occultation predictions,…

Instrumentation and Methods for Astrophysics · Physics 2015-06-23 Dayton L. Jones , William M. Folkner , Robert A. Jacobson , Christopher S. Jacobs , Vivek Dhawan , Jon Romney , Ed Fomalont

We present 5 GHz space-VLBI observations of the quasar pair B1342+662/B1342+663 that demonstrate the feasibility of phase-reference techniques using an antenna in space. The space-based data were taken by the satellite HALCA, of the…

Interferometric imaging is a well established method to image phase objects by mixing the image wavefront with a reference one on a CCD camera. It has also been applied to fast transient phenomena, mostly through the analysis of single…

Accurate primary beam calibration is essential for precise brightness measurements in radio astronomy. The VLA Low-band Ionosphere and Transient Experiment (VLITE) faces challenges in calibration due to the offset Cassegrain optics used in…

Instrumentation and Methods for Astrophysics · Physics 2024-12-20 Emil Polisensky , Tracy E. Clarke , Simona Giacintucci , Wendy Peters

Vision-language models (VLMs) have recently shown promise in general-purpose reasoning tasks, yet their applicability to domain-specific scientific workflows remains largely unexplored. In this work, we evaluated a series of open-weight and…

Instrumentation and Methods for Astrophysics · Physics 2026-02-10 S. Riggi
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