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The emergence of active regions on the Sun is an integral feature of the solar dynamo mechanism. However, details about the generation of active-region-scale magnetism and the journey of this magnetic flux to the photosphere are still in…

Solar and Stellar Astrophysics · Physics 2023-06-13 Maria A. Weber , Hannah Schunker , Laurène Jouve , Emre Işık

Sunspots and active regions observed on the solar surface are widely believed to be manifestations of compact predominantly-toroidal magnetic field structures (``flux tubes") that emerge by magnetic buoyancy from the deeper interior of the…

Solar and Stellar Astrophysics · Physics 2024-06-21 Bhishek Manek , Nicholas Brummell

The quality of images of the Sun obtained from the ground are severely limited by the perturbing effect of the turbulent Earth's atmosphere. The post-facto correction of the images to compensate for the presence of the atmosphere require…

Solar and Stellar Astrophysics · Physics 2018-12-05 A. Asensio Ramos , J. de la Cruz Rodriguez , A. Pastor Yabar

We compare Fourier spectra of photospheric velocity fields from very high resolution IMaX observations to those from recent 3D numerical magnetoconvection models. We carry out a proper comparison by synthesizing spectral lines from the…

Solar and Stellar Astrophysics · Physics 2015-06-18 L. Yelles Chaouche , F. Moreno-Insertis , J. A. Bonet

Spatially-resolved X-ray observations are the key to understanding electron acceleration in solar flares. Currently, the underlying processes that efficiently energize solar flare particles are poorly constrained. Abundant flare…

Solar and Stellar Astrophysics · Physics 2026-03-09 Morgan Stores , Natasha Jeffrey , Ewan Dickson , James McLaughlin , Eduard Kontar

We present MIRReS, a novel two-stage inverse rendering framework that jointly reconstructs and optimizes the explicit geometry, material, and lighting from multi-view images. Unlike previous methods that rely on implicit irradiance fields…

Computer Vision and Pattern Recognition · Computer Science 2025-02-28 Yuxin Dai , Qi Wang , Jingsen Zhu , Dianbing Xi , Yuchi Huo , Chen Qian , Ying He

Ill-posed inverse problems are fundamental in many domains, ranging from astrophysics to medical imaging. Emerging diffusion models provide a powerful prior for solving these problems. Existing maximum-a-posteriori (MAP) or posterior…

Computer Vision and Pattern Recognition · Computer Science 2026-05-15 Minseo Kim , Axel Levy , Gordon Wetzstein

Variations of the solar UV irradiance are an important driver of chemical and physical processes in the Earth's upper atmosphere and may also influence global climate. Here we reconstruct solar UV irradiance in the range 115-400 nm over the…

Solar and Stellar Astrophysics · Physics 2009-11-23 N. A. Krivova , S. K. Solanki , T. Wenzler , B. Podlipnik

This paper investigates the shape reconstructions of sub-wavelength objects from near-field measurements in transverse electromagnetic scattering. This geometric inverse problem is notoriously ill-posed and challenging. We develop a novel…

Mathematical Physics · Physics 2023-05-03 M. H. Ding , H. Y. Liu , G. H. Zheng

We measure the horizontal subsurface flow in a fast emerging active region (NOAA 11158) using the ring-diagram technique and the HMI high-spatial resolution Dopplergrams. This active region had a complex magnetic structure and displayed…

Solar and Stellar Astrophysics · Physics 2015-08-04 Kiran Jain , S. C. Tripathy , F. Hill

The evolution of small magnetic features in quiet regions of the Sun provides a unique window to probing solar magneto-convection. Here we analyze small scale magnetic features in the quiet Sun, using the high resolution, seeing-free…

Solar and Stellar Astrophysics · Physics 2017-02-01 L. S. Anusha , Sami K. Solanki , Johann Hirzberger , Alex Feller

Upflows at the edges of active regions (ARs) are studied by spatially and temporally combining multi-instrument observations obtained with EIS/Hinode, AIA and HMI/SDO and IBIS/NSO, to derive their plasma parameters. This information is used…

Solar and Stellar Astrophysics · Physics 2015-11-18 K. Vanninathan , M. S. Madjarska , K. Galsgaard , Z. Huang , J. G. Doyle

We consider imaging of fast moving small objects in space, such as low earth orbit satellites, which are also rotating around a fixed axis. The imaging system consists of ground based, asynchronous sources of radiation and several passive…

Signal Processing · Electrical Eng. & Systems 2021-11-03 Matan Leibovich , George Papanicolaou , Chrysoula Tsogka

Context: The interaction of plasma motions and magnetic fields is an important mechanism, which drives solar activity in all its facets. For example, photospheric flows are responsible for the advection of magnetic flux, the redistribution…

Solar and Stellar Astrophysics · Physics 2015-05-27 M. Verma , C. Denker

Underwater images suffer from light refraction and absorption, which impairs visibility and interferes the subsequent applications. Existing underwater image enhancement methods mainly focus on image quality improvement, ignoring the effect…

Computer Vision and Pattern Recognition · Computer Science 2023-08-03 Zengxi Zhang , Zhiying Jiang , Jinyuan Liu , Xin Fan , Risheng Liu

To deepen the analysis of the photometric properties of the umbra of a sunspot, we study proper motions of small features such as umbral dots (UDs) inside a single sunspot observed by the Solar Optical Telescope of Hinode close to the disk…

Solar and Stellar Astrophysics · Physics 2018-07-17 Hadis Goodarzi , Serge Koutchmy , Ali Adjabshirizadeh

The flows in and around sunspots are rich in detail. Starting with the Evershed flow along low-lying flow channels, which are cospatial with the horizontal penumbral magnetic fields, Evershed clouds may continue this motion at the periphery…

Solar and Stellar Astrophysics · Physics 2015-05-19 Carsten Denker , Meetu Verma

A wide variety of phenomena such as gentle but persistent brightening, dynamic slender features (~100 km), and compact (~1'') ultraviolet (UV) bursts are associated with the heating of the solar chromosphere. High spatio-temporal resolution…

Solar and Stellar Astrophysics · Physics 2018-10-03 H. N. Smitha , L. P. Chitta , T. Wiegelmann , S. K. Solanki

The flare-prolific active region NOAA 10930 offered both a developing delta-spot and a decaying satellite sunspot of opposite polarity. The objective of this study is to characterize the photometric decay of the satellite sunspot and the…

Solar and Stellar Astrophysics · Physics 2015-06-05 Meetu Verma , Carsten Denker

Wind speed at sea surface is a key quantity for a variety of scientific applications and human activities. Due to the non-linearity of the phenomenon, a complete description of such variable is made infeasible on both the small scale and…

Machine Learning · Computer Science 2024-10-28 Matteo Zambra , Nicolas Farrugia , Dorian Cazau , Alexandre Gensse , Ronan Fablet