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Coronal magnetic fields are well known to be one of the crucial parameters defining coronal physics and space weather. However, measuring the global coronal magnetic fields remains challenging. The polarization properties of coronal radio…

Solar and Stellar Astrophysics · Physics 2022-07-01 Devojyoti Kansabanik , Divya Oberoi , Surajit Mondal

Imaging the low-frequency radio Sun is an intrinsically challenging problem. Meter-wavelength solar emission spans angular scales from a few arcminutes to a few degrees. These emissions show temporal and spectral variability on a sub-second…

Solar and Stellar Astrophysics · Physics 2022-09-22 Devojyoti Kansabanik

Recent instrumentation has demonstrated that the solar atmosphere supports omnipresent transverse waves, which could play a key role in energizing the solar corona. Large-scale studies are required in order to build up an understanding of…

Solar and Stellar Astrophysics · Physics 2018-07-16 Micah J. Weberg , Richard J. Morton , James A. McLaughlin

Magnetic field couples the solar interior to the solar atmosphere, known as the corona. The coronal magnetic field is one of the crucial parameters which determines the coronal structures and regulates the space weather phenomena like…

Solar and Stellar Astrophysics · Physics 2022-07-26 Devojyoti Kansabanik , Divya Oberoi , Surajit Mondal

This work presents new methods and algorithms for tracking the shape and trajectory of moving reflecting obstacles with broken rays, or rays reflecting at an obstacle. While in tomography the focus of the reconstruction method is to recover…

Graphics · Computer Science 2011-11-29 Kamen Lozev

The spatial-frequency coverage of a radio interferometer is increased by combining samples acquired at different times and observing frequencies. However, astrophysical sources often contain complicated spatial structure that varies within…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 U. Rau

We consider the problem of automatically (and robustly) isolating and extracting information about waves and oscillations observed in EUV image sequences of the solar corona with a view to near real-time application to data from the…

Astrophysics · Physics 2009-11-13 Scott W. McIntosh , Bart De Pontieu , Steven Tomczyk

Low frequency imaging radio arrays such as MWA, LWA and LOFAR have been recently commissioned, and significantly more advanced and flexible arrays are planned for the near term. These powerful instruments offer new opportunities for direct…

Instrumentation and Methods for Astrophysics · Physics 2018-02-07 C. Lonsdale , L. Benkevitch , I. Cairns , M. Crowley , P. Erickson , M. Knapp , K. Kozarev , F. Lind , P. McCauley , J. Morgan , D. Oberoi

Recently observed oscillations in the solar atmosphere have been interpreted and modeled as magnetohydrodynamic wave modes. This has allowed the estimation of parameters that are otherwise hard to derive, such as the coronal magnetic-field…

Solar and Stellar Astrophysics · Physics 2010-07-07 Jack Ireland , Michael S. Marsh , Therese A. Kucera , Christopher A. Young

We developed an automated pattern recognition code that is particularly well suited to extract one-dimensional curvi-linear features from two-dimensional digital images. A former version of this {\sl Oriented Coronal CUrved Loop Tracing…

Solar and Stellar Astrophysics · Physics 2013-08-05 Markus J. Aschwanden , Bart De Pontieu , Eugene A. Katrukha

We use rotation stereoscopy to estimate the height of a steady-state solar feature relative to the photosphere, based on its apparent motion in the image plane recorded over several days of observation. The stereoscopy algorithm is adapted…

Solar and Stellar Astrophysics · Physics 2015-05-28 Gelu M. Nita , Gregory D. Fleishman , Ju Jing , Sergey V. Lesovoi , Vladimir M. Bogod , Leonid V. Yasnov , Haimin Wang , Dale E. Gary

We describe a new algorithm for reconstruction of Differential Emission Measures (DEMs) in the solar corona. Although a number of such algorithms currently exist, they can have difficulty converging for some cases, and can be complex, slow,…

Solar and Stellar Astrophysics · Physics 2020-12-11 Joseph Plowman , Amir Caspi

Extreme UltraViolet images of the corona contain information over a large range of spatial scales, and different structures such as active regions, quiet Sun and filament channels contain information at very different brightness regimes.…

Solar and Stellar Astrophysics · Physics 2015-06-19 Huw Morgan , Miloslav Druckmuller

The quantity of small scale solar photovoltaic (PV) arrays in the United States has grown rapidly in recent years. As a result, there is substantial interest in high quality information about the quantity, power capacity, and energy…

Computer Vision and Pattern Recognition · Computer Science 2016-10-03 Jordan M. Malof , Kyle Bradbury , Leslie M. Collins , Richard G. Newell

Solar radio emission, especially at metre-wavelengths, is well known to vary over small spectral ($\lesssim$100\,kHz) and temporal ($<1$\,s) spans. It is comparatively recently, with the advent of a new generation of instruments, that it…

Instrumentation and Methods for Astrophysics · Physics 2019-05-01 Surajit Mondal , Atul Mohan , Divya Oberoi , John S. Morgan , Leonid Benkevitch , Colin J. Lonsdale , Meagan Crowley , Iver H. Cairns

The phenomena observed at the Sun have a variety of unique radio signatures that can be used to diagnose the processes in the solar atmosphere. The insights provided by radio obervations are further enhanced when they are combined with…

Solar and Stellar Astrophysics · Physics 2018-06-26 E. P. Kontar , A. Nindos

Improving irradiance forecasting is critical to further increase the share of solar in the energy mix. On a short time scale, fish-eye cameras on the ground are used to capture cloud displacements causing the local variability of the…

Computer Vision and Pattern Recognition · Computer Science 2022-10-26 Quentin Paletta , Joan Lasenby

Ray tracing algorithm simulates the physical movements of a huge amount of rays to render a high quality image, in which the tracing procedure for each ray can be implemented in parallel. By leveraging the inherent parallelism of quantum…

Quantum Physics · Physics 2022-03-30 Xi Lu , Hongwei Lin

Ray tracing is increasingly utilized in wireless system simulations to estimate channel paths. In large-scale simulations with complex environments, ray tracing at high resolution can be computationally demanding. To reduce the computation,…

Signal Processing · Electrical Eng. & Systems 2026-02-02 Ruibin Chen , Jayadev Joy , Yaqi Hu , Mingsheng Yin , Marco Mezzavilla , Sundeep Rangan

This work develops novel algorithms for high-performance networking in the presence of obstacles based on a method for communicating via ultrasonic rays reflected at the obstacles. The rays are curves determined by the variable speed of…

Networking and Internet Architecture · Computer Science 2012-07-09 Kamen Lozev
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