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Related papers: Alfven Waves in the Lower Solar Atmosphere

200 papers

We study the role the the p-mode-like vertical oscillation on the photosphere in driving solar winds in the framework of Alfven-wave-driven winds. By performing one-dimensional magnetohydrodynamical numerical simulations from the…

Solar and Stellar Astrophysics · Physics 2022-11-10 Kimihiko Shimizu , Munehito Shoda , Takeru K. Suzuki

Waves and oscillations are important solar phenomena, not only because they can propagate and dissipate energy in the chromosphere, but also because they carry information about the structure of the atmosphere in which they propagate. The…

Solar and Stellar Astrophysics · Physics 2022-01-26 Yi Chai , Dale E. Gary , Kevin P. Reardon , Vasyl Yurchyshyn

Alfvenic waves are thought to play an important role in coronal heating and solar wind acceleration. Here we investigate the dissipation of standing Alfven waves due to phase mixing at the presence of steady flow and sheared magnetic field…

Solar and Stellar Astrophysics · Physics 2015-06-15 Z. Fazel , H. Ebadi

On the basis of observations of solar granulation obtained with the New Solar Telescope (NST) of Big Bear Solar Observatory, we explored proper motion of bright points (BPs) in a quiet sun area, a coronal hole, and an active region plage.…

Solar and Stellar Astrophysics · Physics 2011-11-21 V. I. Abramenko , V. Carbone , V. Yurchyshyn , P. R. Goode , R. F. Stein , F. Lepreti , V. Capparelli , A. Vecchio

Solar torsional oscillations are migrating bands of slower- and faster-than-average rotation, which are strongly related to the Sun's magnetic cycle. We perform a long-term study (16 yr) of hemispherical asymmetry in solar torsional…

Solar and Stellar Astrophysics · Physics 2018-08-01 Lekshmi B , Dibyendu Nandy , H M Antia

Cool stars at giant and supergiant evolutionary phases present low velocity and high density winds, responsible for the observed high mass-loss rates. Although presenting high luminosities, radiation pressure on dust particles is not…

Astrophysics · Physics 2009-11-11 D. Falceta-Goncalves , A. A. Vidotto , V. Jatenco-Pereira

Planetary-scale waves at the Venusian cloud-top cause periodic variations in both winds and ultraviolet (UV) brightness. While the wave candidates are the 4-day Kelvin wave and 5-day Rossby wave with zonal wavenumber 1, their temporal…

We investigate several key questions of plasma heating in open-field regions of the corona that connect to the solar wind. We present results for a model of Alfven-wave-driven turbulence for three typical open magnetic field structures: a…

Solar and Stellar Astrophysics · Physics 2015-10-07 Lauren N. Woolsey , Steven R. Cranmer

Helioseismic and magnetohydrodynamic waves are abundant in and above sunspots. Through cross-correlating oscillation signals in the photosphere observed by the SDO/HMI, we reconstruct how waves propagate away from virtual wave sources…

Solar and Stellar Astrophysics · Physics 2015-08-19 Junwei Zhao , Ruizhu Chen , Thomas Hartlep , Alexander G. Kosovichev

We characterize waves in small magnetic elements and investigate their propagation in the lower solar atmosphere from observations at high spatial and temporal resolution. We use the wavelet transform to analyze oscillations of both…

Solar and Stellar Astrophysics · Physics 2017-03-31 Shahin Jafarzadeh , S. K. Solanki , M. Stangalini , O. Steiner , R. H. Cameron , S. Danilovic

Recent progress in instrumentation enables solar observations with high resolution simultaneously in the spatial, temporal, and spectral domains. We use such high-resolution observations to study small-scale structures and dynamics in the…

Solar and Stellar Astrophysics · Physics 2015-05-14 Sven Wedemeyer-Böhm , Luc Rouppe van der Voort

Oscillation properties in two sunspots and two facular regions are studied using Solar Dynamics Observatory (SDO) data and ground-based observations in the SiI 10827 and HeI 10830 lines. The aim is to study different-frequency spatial…

Solar and Stellar Astrophysics · Physics 2014-11-25 N. I. Kobanov , D. Y. Kolobov , A. A. Chelpanov

The Coronal Multi-channel Polarimeter (CoMP) has previously demonstrated the presence of Doppler velocity fluctuations in the solar corona. The observed fluctuations are thought to be transverse waves, i.e. highly incompressible motions…

Solar and Stellar Astrophysics · Physics 2016-09-21 R. J. Morton , S. Tomczyk , R. F. Pinto

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

This paper is devoted to the study of the gravitational instability of a medium permeated by a uniform magnetic field along which a circularly polarized Alfven wave propagates. We concentrate on the case of perturbations purely transverse…

Astrophysics · Physics 2009-11-07 Adriana Gazol , Thierry Passot

In the present work, we test the predictions of the AWSoM model, a global extended-MHD model capable of calculating the propagation and turbulent dissipation of Alfv\'en waves in any magnetic topology, against high resolution spectra of the…

Solar and Stellar Astrophysics · Physics 2014-01-06 R. Oran , E. Landi , B. van der Holst , I. V. Sokolov , T. I. Gombosi

We studied waves seen during the class C1.9 flare that occurred in Active Region NOAA 11272 on SOL2011-08-17. We found standing waves with periods in the 9- and 19-minute band in six extreme ultraviolet (EUV) wavelengths of the SDO/AIA…

Solar and Stellar Astrophysics · Physics 2016-11-29 S. M. Conde Cuellar , J. E. R. Costa , C. E. Cedeño Montaña

We revisit the role of longitudinal waves in driving the solar wind. We study how the the $p$-mode-like vertical oscillation on the photosphere affects the properties of solar winds under the framework of Alfv\'en-wave-driven winds. We…

Solar and Stellar Astrophysics · Physics 2022-09-14 Kimihiko Shimizu , Munehito Shoda , Takeru K. Suzuki

In this study we combine the multiwavelength ultraviolet -- optical (Solar Dynamics Observatory, SDO) and radio (Nobeyama Radioheliograph, NoRH) observations to get further insight into space-frequency distribution of oscillations at…

Solar and Stellar Astrophysics · Physics 2015-05-13 D. Y. Kolobov , N. I. Kobanov , A. A. Chelpanov , A. A. Kochanov , S. A. Anfinogentov , S. A. Chupin , I. I. Myshyakov , V. E. Tomin

The characteristics of Alfv\'en waves propagating in a direction oblique to the ambient magnetic field in a stellar wind environment are discussed. A kinetic formulation for a magnetized dusty plasma is adopted considering Maxwellian…

Plasma Physics · Physics 2022-03-22 L. B. De Toni , R. Gaelzer , L. F. Ziebell
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