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Numerous vector angular spectrum methods have been presented to model the vectorial nature of diffractive electromagnetic field, facilitating optical field engineering in polarization-related and high numerical aperture systems. However,…

Optics · Physics 2025-09-29 Chengda Song , Jing He , Guanghui Yuan

Twisted coronal loops should be ubiquitous in the solar corona. Twisted magnetic fields contain excess magnetic energy, which can be released during magnetic reconnection, causing solar flares. The aim of this work is to investigate…

Solar and Stellar Astrophysics · Physics 2015-01-27 Mykola Gordovskyy , Philippa Browning , Eduard Kontar , Nicolas Bian

Solar inertial modes are quasi-toroidal modes of the Sun that are of practical interest as they allow probing the deep convection zone. Since 2010, solar images of the photospheric magnetic field are made available by HMI onboard the Solar…

Solar and Stellar Astrophysics · Physics 2025-02-10 Neelanchal Joshi , Zhi-Chao Liang , Damien Fournier , Laurent Gizon

We present a study of the line-of-sight magnetic fields in five large-diameter Galactic HII regions. Using the Faraday rotation of background polarized radio sources, as well as dust-corrected H-alpha surface brightness as a probe of…

Astrophysics of Galaxies · Physics 2015-05-28 Lisa Harvey-Smith , Gregory J. Madsen , Bryan M. Gaensler

We probe the three-dimensional geometry of the large-scale Galactic magnetic field within 1 kpc of the Sun using the Dominion Radio Astrophysical Observatory (DRAO) Global Magneto-Ionic Medium Survey (GMIMS) of the Northern Sky (DRAGONS).…

Recent advances have made it possible to obtain two-dimensional line-of-sight magnetic field maps of the solar corona from spectropolarimetric observations of the Fe XIII 1075 nm forbidden coronal emission line. Together with the linear…

Astrophysics · Physics 2009-11-13 Yu Liu , Haosheng Lin

Faraday rotation of polarised background sources is a unique probe of astrophysical magnetic fields in a diverse range of foreground objects. However, to understand the properties of the polarised sources themselves and of depolarising…

The solar corona is host to a continuous flow of propagating disturbances (PD). These are continuous and ubiquitous across broad regions of the corona, including the quiet Sun. The aim of this paper is to present an improved, efficient…

Solar and Stellar Astrophysics · Physics 2022-08-31 Huw Morgan , Marianna Korsos

We propose a simple relativistic derivation of the electric and the magnetic fields generated by an electric point charge moving with constant velocity. Our approach is based on the radar detection of the point space coordinates where the…

General Physics · Physics 2008-12-02 Bernhard Rothenstein , Stefan Popescu , George J. Spix

We present in this Letter the first global comparison between traditional line-tied steady state magnetohydrodynamic models and a new, fully time-dependent thermodynamic magnetohydrodynamic simulation of the global corona. The maps are…

Solar and Stellar Astrophysics · Physics 2023-06-22 Emily I. Mason , Roberto Lionello , Cooper Downs , Jon A. Linker , Ronald M. Caplan

Measurements of the Faraday rotation of the cosmic microwave background radiation (CMBR) polarization could provide evidence for the existence of primordial magnetic fields. The Faraday rotation could also allow the study of some properties…

Astrophysics · Physics 2009-11-10 L. Campanelli , A. D. Dolgov , M. Giannotti , F. L. Villante

Accurate modeling of the Sun's coronal magnetic field and solar wind structures require inputs of the solar global magnetic field, including both the near and far sides, but the Sun's far-side magnetic field cannot be directly observed.…

Solar and Stellar Astrophysics · Physics 2023-01-04 Ruizhu Chen , Junwei Zhao , Shea Hess Webber , Yang Liu , J. Todd Hoeksema , Marc L. Derosa

Using one-dimensional models, we show that a helical magnetic field with an appropriate sign of helicity can compensate the Faraday depolarization resulting from the superposition of Faraday-rotated polarization planes from a spatially…

Cosmology and Nongalactic Astrophysics · Physics 2014-04-23 Axel Brandenburg , Rodion Stepanov

In many applications it is important to estimate a fluid flow field from limited and possibly corrupt measurements. Current methods in flow estimation often use least squares regression to reconstruct the flow field, finding the…

Fluid Dynamics · Physics 2019-11-06 Jared Callaham , Kazuki Maeda , Steven L. Brunton

Coupled flux transport and magneto-frictional simulations are extended to simulate the continuous magnetic field evolution in the global solar corona for over 15 years, from the start of Solar Cycle 23 in 1996. By simplifying the dynamics,…

Solar and Stellar Astrophysics · Physics 2015-06-15 A. R. Yeates

In this paper we develop theoretical analysis and numerical reconstruction techniques for the solution of an inverse boundary value problem dealing with the nonlinear, time-dependent monodomain equation, which models the evolution of the…

Analysis of PDEs · Mathematics 2017-01-27 Elena Beretta , Cecilia Cavaterra , Maria Cristina Cerutti , Andrea Manzoni , Luca Ratti

Non-linear force-free fields are the most general case of force-free fields, but the hardest to model as well. There are numerous methods of computing such fields by extrapolating vector magnetograms from the photosphere, but very few…

Solar and Stellar Astrophysics · Physics 2021-06-29 A. Malanushenko , D. W. Longcope , D. E. McKenzie

The inverse problem which consists of determining the flow at the Earth's Core Mantle Boundary according to an outer core magnetic field and secular variation model, has been investigated through a Bayesian formalism. To circumvent the…

Geophysics · Physics 2015-06-17 Julien Baerenzung , Matthias Holschneider , Vincent Lesur

Extrapolation codes in Cartesian geometry for modelling the magnetic field in the corona do not take the curvature of the Sun's surface into account and can only be applied to relatively small areas, e.g., a single active region. We compare…

Solar and Stellar Astrophysics · Physics 2015-06-11 Tilaye Tadesse , T. Wiegelmann , B. Inhester , P. MacNeice , A. Pevtsov , X. Sun

Space-based coronagraphs for future earth-like planet detection will require focal plane wavefront control techniques to achieve the necessary contrast levels. These correction algorithms are iterative and the control methods require an…

Instrumentation and Methods for Astrophysics · Physics 2015-06-11 Tyler D. Groff , N. Jeremy Kasdin