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We performed 2.5D magnetohydrodynamic (MHD) simulations showing the propagation of fast-mode MHD waves of different initial amplitudes and their interaction with a coronal hole (CH), using our newly developed numerical code. We find that…

Large-scale structure projections are an obstacle in converting the shear signal of clusters detected in weak-lensing maps into virial masses. However, this step is not necessary for constraining cosmology with the shear-peak abundance, if…

Cosmology and Nongalactic Astrophysics · Physics 2014-11-20 Laura Marian , Robert E. Smith , Gary M. Bernstein

Coronal bright points (BPs) are small-scale luminous features seen in the solar corona. Quasi-periodic brightenings are frequently observed in the BPs and are generally linked with underneath magnetic flux changes. We study the dynamics of…

Solar and Stellar Astrophysics · Physics 2015-05-05 Tanmoy Samanta , Dipankar Banerjee , Hui Tian

We have performed a three-dimensional magnetohydrodynamic simulation to study the emergence of a twisted magnetic flux tube from -20,000 km of the solar convection zone to the corona through the photosphere and the chromosphere. The middle…

Solar and Stellar Astrophysics · Physics 2015-06-03 S. Toriumi , T. Yokoyama

The observed solar activity is believed to be driven by the dissipation of nonpotential magnetic energy injected into the corona by dynamic processes in the photosphere. The enormous range of scales involved in the interaction makes it…

Solar and Stellar Astrophysics · Physics 2015-06-12 Vadim M. Uritsky , Joseph M. Davila , Leon Ofman , Aaron J. Coyner

We study the influence of the spatial resolution on scales of $5\deg$ and smaller of solar surface magnetic field maps on global magnetohydrodynamic solar wind models, and on a model of coronal heating and X-ray emission. We compare the…

Solar and Stellar Astrophysics · Physics 2013-05-13 C. Garraffo , O. Cohen , J. J. Drake , C. Downs

Measurement of the coronal magnetic field is a crucial ingredient in understanding the nature of solar coronal dynamic phenomena at all scales. We employ STEREO/COR1 data obtained near maximum of solar activity in December 2012 (Carrington…

Solar and Stellar Astrophysics · Physics 2016-04-05 Maxim Kramar , Vladimir Airapetian , Haosheng Lin

Global magnetic field models use as input synoptic data, which usually show "aging effects" as the longitudinal 360{\deg} information is not obtained simultaneously. Especially during times of increased solar activity, the evolution of the…

Solar and Stellar Astrophysics · Physics 2021-10-04 Stephan G. Heinemann , Manuela Temmer , Stefan J. Hofmeister , Aleksandar Stojakovic , Laurent Gizon , Dan Yang

We report the first unambiguous observational evidence in the radio range of the reflection of a coronal shock wave at the boundary of a coronal hole. The event occurred above an active region located at the northwest limb of the Sun and…

Solar and Stellar Astrophysics · Physics 2021-07-28 S. Mancuso , A. Bemporad , F. Frassati , D. Barghini , S. Giordano , D. Telloni , C. Taricco

Using advanced processing techniques, we analyze high-cadence, high-resolution extreme ultraviolet images and show that, throughout the solar cycle, mid-latitude coronal holes (CHs) are made up of ubiquitous and space-filling funnel-shaped…

Solar and Stellar Astrophysics · Physics 2025-08-06 Nathalia Alzate , Simone Di Matteo , Aleida Higginson

Coronal rain consists of cool and dense plasma condensations formed in coronal loops as a result of thermal instability. Previous numerical simulations of thermal instability and coronal rain formation have relied on artificially adding a…

Solar and Stellar Astrophysics · Physics 2020-07-08 P. Kohutova , P. Antolin , A. Popovas , M. Szydlarski , V. H. Hansteen

A large part of the hot corona consists of magnetically confined, bright plasma loops. These observed loops are in turn structured into bright strands. We investigate the relationship between magnetic field geometry, plasma properties and…

Solar and Stellar Astrophysics · Physics 2025-12-22 C. A. Breu , D. I. Pontin , E. Priest , I. De Moortel

Observations from the NASA Solar Dynamic Observatory Atmospheric Imaging Assembly were employed to investigate targeted physical properties of coronal active region structures across the entirety of Solar Cycle 24 (dates). This is the…

Solar and Stellar Astrophysics · Physics 2023-05-19 Daniel Gordon Gass , Robert William Walsh

We present the results of a detailed numerical simulation of the circumstellar environment around three exoplanet-hosting stars. A state-of-the-art global magnetohydrodynamic (MHD) model is considered, including Alfv\'en wave dissipation as…

Solar and Stellar Astrophysics · Physics 2016-03-16 J. D. Alvarado-Gómez , G. A. J. Hussain , O. Cohen , J. J. Drake , C. Garraffo , J. Grunhut , T. I. Gombosi

One puzzling observed property of coronal loops is that they are of roughly constant thickness along their length. Various studies have found no consistent pattern of width variation along the length of loops observed by TRACE and SOHO.…

Solar and Stellar Astrophysics · Physics 2009-11-13 Joseph E. Plowman , Charles C. Kankelborg , Dana W. Longcope

Coronal loops are the basic building block of the upper solar atmosphere. Comprehending how these are energized, structured, and evolve is key to understanding stellar coronae. Here we investigate how the energy to heat the loop is…

Solar and Stellar Astrophysics · Physics 2022-02-09 C. Breu , H. Peter , R. Cameron , S. K. Solanki , D. Przybylski , M. Rempel , L. P. Chitta

Srivastava et al. (2010) have observed a highly twisted coronal loop, which was anchored in AR10960 during the period 04:43 UT-04:52 UT on 4 June 2007. The loop length and radius are approximately 80 Mm and 4 Mm, with a twist of 11.5 $\pi$.…

Solar and Stellar Astrophysics · Physics 2015-06-12 A. K. Srivastava , G. J. J. Botha , T. D. Arber , P. Kayshap

We intend to investigate the underlying physics for the coronal rain phenomenon in a representative bipolar magnetic field, including the formation and the dynamics of coronal rain blobs. With the MPI-AMRVAC code, we performed three…

Solar and Stellar Astrophysics · Physics 2017-07-05 Chun Xia , Rony Keppens , Xia Fang

The "middle corona" is a critical transition between the highly disparate physical regimes of the lower and outer solar corona. Nonetheless, it remains poorly understood due to the difficulty of observing this faint region (1.5-3 solar…

Simulations of light scattering off an extreme ultraviolet lithography mask with a 2D-periodic absorber pattern are presented. In a detailed convergence study it is shown that accurate results can be attained for relatively large 3D…

Optics · Physics 2011-05-31 S. Burger , L. Zschiedrich , J. Pomplun , F. Schmidt