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The determination of horizontal velocity fields at the solar surface is crucial to understanding the dynamics and magnetism of the convection zone of the sun. These measurements can be done by tracking granules. Tracking granules from…

Astrophysics · Physics 2009-11-13 R. Tkaczuk , M. Rieutord , N. Meunier , T. Roudier

Polarimetric radio observations of the Sun can provide rich information about emission mechanisms and the propagation medium. For the past five decades, solar polarimetric studies at low radio frequencies have almost always assumed the…

Solar and Stellar Astrophysics · Physics 2025-08-05 Soham Dey , Devojyoti Kansabanik , Divya Oberoi , Surajit Mondal

Low-frequency radio observations have been expected to serve as a powerful tool for Space Weather (SW) observations for decades. Radio observations are sensitive to a wide range of SW-related observations ranging from emissions from coronal…

Solar and Stellar Astrophysics · Physics 2023-02-01 Devojyoti Kansabanik , Surajit Mondal , Divya Oberoi , Puja Majee

We present a new method that combines the results of an oscillation study made in optical and radio observations. The optical spectral measurements in photospheric and chromospheric lines of the line-of-sight velocity were carried out at…

Solar and Stellar Astrophysics · Physics 2015-03-18 V. E. Abramov-Maximov , G. B. Gelfreikh , N. I. Kobanov , K. Shibasaki , S. A. Chupin

Ahead-of-time forecasting of the output power of power plants is essential for the stability of the electricity grid and ensuring uninterrupted service. However, forecasting renewable energy sources is difficult due to the chaotic behavior…

Computer Vision and Pattern Recognition · Computer Science 2023-10-27 Anas Al-lahham , Obaidah Theeb , Khaled Elalem , Tariq A. Alshawi , Saleh A. Alshebeili

We present a new algorithm for multi-region segmentation of 2D images with objects that may partially occlude each other. Our algorithm is based on the observation hat human performance on this task is based both on prior knowledge about…

Computer Vision and Pattern Recognition · Computer Science 2016-06-16 Yuka Kihara , Matvey Soloviev , Tsuhan Chen

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

Detection of (ultra-) high-energy cosmic rays with the use of radio frequency emission from extensive air showers has been proven as complimentary to existing ground array detection techniques. Great progress has been made in the…

Instrumentation and Methods for Astrophysics · Physics 2019-08-13 Sijbrand de Jong

A new code for evaluation of light absorption and scattering by interstellar dust grains is presented. The radiative transfer problem is solved using ray-tracing algorithm in a self-consistent and highly efficient way. The code demonstrates…

Astrophysics · Physics 2007-05-23 D. Semionov , V. Vansevicius

The broadband analog-digital heliograph based on the UTR-2 radio telescope is described in detail. This device operates by employing the parallel-series principle when five equi-spaced array pattern beams which scan the given radio source…

Instrumentation and Methods for Astrophysics · Physics 2011-12-06 Aleksander Stanislavsky , Artem Koval , Aleksander Konovalenko , Eduard Abranin

We present techniques developed to calibrate and correct Murchison Widefield Array (MWA) low frequency (72-300 MHz) radio observations for polarimetry. The extremely wide field-of-view, excellent instantaneous (u, v)-coverage and…

Site-specific radio frequency (RF) propagation prediction increasingly relies on models built from visual data such as cameras and LIDAR sensors. When operating in dynamic settings, the environment may only be partially observed. This paper…

Robotics · Computer Science 2022-07-05 Mingsheng Yin , Yaqi Hu , Tommy Azzino , Seongjoon Kang , Marco Mezzavilla , Sundeep Rangan

We present $\texttt{moes}$, a ray tracing software package that computes the path of rays through echelle spectrographs. Our algorithm is based on sequential direct tracing with Seidel aberration corrections applied at the detector plane.…

Instrumentation and Methods for Astrophysics · Physics 2024-05-01 Marcelo Tala Pinto , Adrian Kaminski , Andreas Quirrenbach , Mathias Zechmeister

We present a procedure for efficiently compressing astronomical radio data for high performance applications. Integrated, post-correlation data are first passed through a nearly lossless rounding step which compares the precision of the…

Object detection in astronomical images, generically referred to as source finding, is often performed before the object characterisation stage in astrophysical processing work flows. In radio astronomy, source finding has historically been…

Instrumentation and Methods for Astrophysics · Physics 2019-01-16 Luis Lucas , Tim Staley , Anna Scaife

We describe a new multi-scale deconvolution algorithm that can also be used in multi-frequency mode. The algorithm only affects the minor clean loop. In single-frequency mode, the minor loop of our improved multi-scale algorithm is over an…

Instrumentation and Methods for Astrophysics · Physics 2017-08-02 A. R. Offringa , O. Smirnov

We investigate the correlations in galaxy shapes between optical and radio wavelengths using archival observations of the COSMOS field. Cross-correlation studies between different wavebands will become increasingly important for precision…

Astrophysics of Galaxies · Physics 2016-12-19 Ben Tunbridge , Ian Harrison , Michael L. Brown

Knowing the behavior of solar radiation at a geographic location is essential for the use of energy from the sun using photovoltaic systems; however, the number of stations for measuring meteorological parameters and for determining the…

Machine Learning · Computer Science 2022-04-13 Luis Eduardo Ordoñez Palacios , Víctor Bucheli Guerrero , Hugo Ordoñez

We develop a new relativistic radiation hydrodynamics code based on the Monte-Carlo algorithm. In this code, we implement a new scheme to achieve the second-order accuracy in time in the limit of a large packet number for solving the…

High Energy Astrophysical Phenomena · Physics 2023-02-15 Kyohei Kawaguchi , Sho Fujibayashi , Masaru Shibata

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 JiangPei Dou , DeQing Ren , YongTian Zhu , Xi Zhang
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