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Related papers: Reconstruction of Fine Scale Auroral Dynamics

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We introduce a probabilistic diffusion-based method for global atmospheric downscaling implemented within the Anemoi framework. The approach transforms low-resolution ensemble forecasts into high-resolution ensembles by learning the…

Driven-dissipative systems often exhibit self-organization in the form of coherent dissipative structures. However, observing such critical states in natural plasmas remains elusive, leading to the traditional view that the fine structure…

A 3D tomographic reconstruction technique is described for inversion of a set of limited-angle high-resolution 2D visible light emission projections (extended in the vertical and toroidal directions) of global MHD eigenmodes in the H-1NF…

Plasma Physics · Physics 2014-08-29 S. R. Haskey , B. D. Blackwell , B. Seiwald , J. Howard

The Atmospheric Imaging Assembly in the Solar Dynamics Observatory provides full Sun images every 1 seconds in each of 7 Extreme Ultraviolet passbands. However, for a significant amount of these images, saturation affects their most intense…

Instrumentation and Methods for Astrophysics · Physics 2015-09-02 Gabriele Torre , Richard A Schwartz , Federico Benvenuto , Anna Maria Massone , Michele Piana

A tomographic method is described to quantify the three-dimensional power-spectrum of the ionospheric electron-density fluctuations based on radio-interferometric observations by a two-dimensional planar array. The method is valid to…

Instrumentation and Methods for Astrophysics · Physics 2015-05-18 L. V. E. Koopmans

Some optical measurements require relative timing of intensity variations with accuracy much finer than the camera frame period. One motivating example is dynamic aurora, where different prompt emissions are expected to originate from…

Space Physics · Physics 2026-05-29 Juha Vierinen , Pavithiran Sivasothy , Björn Gustavsson

The presence of very few statistical studies on auroral omega bands motivated us to test-use a semi-automatic method for identifying large-scale undulations of the diffuse aurora boundary and to investigate their occurrence. Five identical…

Space Physics · Physics 2017-10-19 Noora Partamies , James M. Weygand , Liisa Juusola

We investigate the inverse source problem for the wave equation, arising in photo- and thermoacoustic tomography. There exist quite a few theoretically exact inversion formulas explicitly expressing solution of this problem in terms of the…

Analysis of PDEs · Mathematics 2018-08-01 Ngoc Do , Leonid Kunyansky

Directly imaging Earth-like exoplanets (``exoEarths'') with a coronagraph instrument on a space telescope requires a stable wavefront with optical path differences limited to tens of picometers RMS during exposure times of a few hours.…

This paper presents reconstructions of homogeneous targets from the 2D and 3D Fresnel databases by one-step imaging methods based on the computation of topological derivative and topological energy fields. The electromagnetic inverse…

Analysis of PDEs · Mathematics 2025-01-28 A. Carpio , M. Pena , M. L. Rapún

The photoionization-driven evaporation of planetary atmospheres has emerged as a potentially fundamental process for planets on short period orbits. While 1-D studies have proven the effectiveness of stellar fluxes at altering the…

Earth and Planetary Astrophysics · Physics 2018-12-19 Alex Debrecht , Jonathan Carroll-Nellenback , Adam Frank , John McCann , Ruth Murray-Clay , Eric G. Blackman

We present a study of wave processes in the sunspot region NOAA 12670 on 2017 August 10 observed by the Goode Solar Telescope in the TiO 7057 A and Ha 6563 A spectral lines. To study the distribution of power oscillations and their…

Solar and Stellar Astrophysics · Physics 2020-01-15 Robert Sych , Yuzef Zhugzhda , Xiaoli Yan

Efforts to push the spatiotemporal imaging-resolution limits of femtosecond (fs) laser-driven ultrafast electron microscopes (UEMs) to the combined angstrom-fs range will benefit from stable sources capable of generating high bunch charges.…

Materials Science · Physics 2024-09-25 Jialiang Chen , Simon A. Willis , David J. Flannigan

We introduce a novel technique to mitigate the adverse effects of atmospheric turbulence on astronomical imaging. Utilizing a video-to-image neural network trained on simulated data, our method processes a sliding sequence of short-exposure…

Instrumentation and Methods for Astrophysics · Physics 2024-05-09 Spencer Bialek , Emmanuel Bertin , Sébastien Fabbro , Hervé Bouy , Jean-Pierre Rivet , Olivier Lai , Jean-Charles Cuillandre

We describe a new concept to correct for scintillation noise on high-precision photometry in large and extremely large telescopes using telemetry data from adaptive optics (AO) systems. Most wide-field AO systems designed for the current…

Instrumentation and Methods for Astrophysics · Physics 2014-11-25 James Osborn

Interferometric observations of the Sun with ALMA provide valuable diagnostic tools for studying the small-scale dynamics of the solar atmosphere. Estimations of the observability of the small-scale dynamics as a function of spatial…

Solar and Stellar Astrophysics · Physics 2021-12-08 Henrik Eklund , Sven Wedemeyer , Mikołaj Szydlarski , Shahin Jafarzadeh

Uplink pre-compensation in ground-to-satellite optical links remains a problem, with an appropriate measurement of the wavefront error in the uplink path often not being available. We present a method that uses successive measurements of…

Instrumentation and Detectors · Physics 2025-09-12 Alex Frost , Nicolas Maron , Shane Walsh , Benjamin Dix-Matthews , Sascha Schediwy , Michael Hart

Schemes for X-ray imaging single protein molecules using new x-ray sources, like x-ray free electron lasers (XFELs), require processing many frames of data that are obtained by taking temporally short snapshots of identical molecules, each…

Data Analysis, Statistics and Probability · Physics 2015-06-17 Kartik Ayyer , Hugh T. Philipp , Mark W. Tate , Veit Elser , Sol M. Gruner

We present a sophisticated statistical point-source foreground model for low-frequency radio Epoch of Reionization (EoR) experiments using the 21 cm neutral hydrogen emission line. Motivated by our understanding of the low-frequency radio…

Cosmology and Nongalactic Astrophysics · Physics 2017-08-16 Steven G. Murray , Cathryn M. Trott , Christopher H. Jordan

We have determined the spatiotemporal characteristics of the magnetosphere-ionosphere (M-I) coupling using auroral imaging. Observations at fixed positions for an extended period of time are provided by a ground-based all-sky imager…

Space Physics · Physics 2017-06-07 B. K. Humberset , J. W. Gjerloev , M. Samara , R. G. Michell
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