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Related papers: Algorithm for Tracing Radio Rays in Solar Corona a…

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Solar radio observations provide a unique diagnostic of the outer solar atmosphere. However, the inhomogeneous turbulent corona strongly affects the propagation of the emitted radio waves, so decoupling the intrinsic properties of the…

Solar and Stellar Astrophysics · Physics 2018-02-22 E. P. Kontar , S. Yu , A. A. Kuznetsov , A. G. Emslie , B. Alcock , N. L. S. Jeffrey , V. N. Melnik , N. H. Bian , P. Subramanian

Over the last years, radio detection has matured to become a competitive method for the detection of air showers. Arrays of thousands of antennas are now envisioned for the detection of cosmic rays of ultra high energy or neutrinos of…

This work describes a novel radiation algorithm designed to capture the three-dimensional, space-time resolved electromagnetic field structure emitted by large ensembles of charged particles. % in particle-in-cell (PIC) codes. The algorithm…

Computational Physics · Physics 2023-03-01 M. Pardal , A. Sainte-Marie , A. Reboul-Salze , R. A. Fonseca , J. Viera

Image alignment plays a crucial role in solar physics research, primarily involving translation, rotation, and scaling. \G{The different wavelength images of the chromosphere and transition region have structural complexity and differences…

Instrumentation and Methods for Astrophysics · Physics 2025-03-17 Yun Wang , KaiFan Ji , Zhenyu Jin , Hui Liu

Nowadays the geometric approach in optics is often used to find out media parameters based on propagation paths of the rays because in this case it is a direct problem. However inverse problem in the framework of geometrical optics is…

Complex field measurements are increasingly becoming the standard for state-of-the-art astronomical instrumentation. Complex field measurements have been used to characterize a suite of ground, airborne, and space-based heterodyne receiver…

Instrumentation and Methods for Astrophysics · Physics 2018-09-25 Kristina K. Davis , Willem Jellema , Stephen J. C. Yates , Christopher E. Groppi , Jochem J. A. Baselmans , Andrey M. Baryshev

The physical world consists of spatially varying media, such as the atmosphere and the ocean, in which light and sound propagates along non-linear trajectories. This presents a challenge to existing ray-tracing based methods, which are…

Graphics · Computer Science 2014-09-16 Qi Mo , Hengchin Yeh , Dinesh Manocha

I present a new algorithm, CALCLENS, for efficiently computing weak gravitational lensing shear signals from large N-body light cone simulations over a curved sky. This new algorithm properly accounts for the sky curvature and boundary…

Cosmology and Nongalactic Astrophysics · Physics 2012-10-15 Matthew R. Becker

The radio detection method for cosmic rays relies on coherent emission from electrons and positrons which is beamed in a narrow cone along the shower axis. Currently the only mod- els to reproduce this emission with sufficient accuracy are…

High Energy Astrophysical Phenomena · Physics 2017-08-09 David Butler , Tim Huege , Olaf Scholten

We report first results from an ongoing program of combining visibilities from the Giant Meterwave Radio Telescope (GMRT) and the Nancay Radio Heliograph (NRH) to produce composite snapshot images of the sun at meter wavelengths. We…

Understanding how the solar corona is structured is of fundamental importance to determining how the Sun's upper atmosphere is heated to high temperatures. Recent spectroscopic studies have suggested that an instrument with a spatial…

Solar and Stellar Astrophysics · Physics 2013-07-18 David H. Brooks , Harry P. Warren , Ignacio Ugarte-Urra , Amy R. Winebarger

The past decade and a half has seen the design and execution of several ground-based spectroscopic surveys, both Galactic and Extra-galactic. Additionally, new surveys are being designed that extend the boundaries of current surveys. In…

Instrumentation and Methods for Astrophysics · Physics 2016-06-15 G. R. Ruchti , S. Feltzing , K. Lind , E. Caffau , A. J. Korn , O. Schnurr , C. J. Hansen , A. Koch , L. Sbordone , R. S. de Jong

Radio observations grant access to a wide range of physical processes through different emission mechanisms. These processes range from thermal and quiescent to eruptive phenomena, such as shock waves and particle beams. We present a new…

In this work we use solar observations with the ALMA radio telescope at the wavelength of 1.21 mm. The aim of the analysis is to improve understanding of the solar chromosphere, a dynamic layer in the solar atmosphere between the…

Solar and Stellar Astrophysics · Physics 2018-12-19 R. Brajša , D. Sudar , I. Skokic , A. O. Benz , M. Kuhar , A. Kobelski , S. Wedemeyer , S. M. White , H. -G. Ludwig , M. Temmer , S. H. Saar , C. L. Selhorst

Extreme ultraviolet (EUV) waves are large-scale propagating disturbances observed in the solar corona, frequently associated with coronal mass ejections and flares. They appear as faint, extended structures propagating from a source region…

Recently, Differentiable Ray Tracing has been successfully applied in the field of wireless communications for learning radio materials or optimizing the transmitter orientation. However, in the frame of gradient based optimization,…

Signal Processing · Electrical Eng. & Systems 2024-04-30 Jerome Eertmans , Laurent Jacques , Claude Oestges

The Sun has remained a difficult source to image for radio telescopes, especially at the low radio frequencies. Its morphologically complex emission features span a large range of angular scales, emission mechanisms involved and brightness…

In recent years, deep learning has been successfully applied in various scientific domains. Following these promising results and performances, it has recently also started being evaluated in the domain of radio astronomy. In particular,…

Next generation communication systems require accurate beam alignment to counteract the impairments that characterize propagation in high-frequency bands. The overhead of the pilot sequences required to select the best beam pair is…

Signal Processing · Electrical Eng. & Systems 2024-02-27 Tien Ngoc Ha , Daniel Romero , Roberto López-Valcarce

Solar radio bursts are some of the brightest emissions at radio frequencies in the solar system. The emission mechanisms that generate these bursts offer a remote insight into physical processes in solar coronal plasma, while fine spectral…

Solar and Stellar Astrophysics · Physics 2024-01-10 Pearse C. Murphy , Baptiste Cecconi , Carine Briand , Stéphane Aicardi