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Related papers: Spectropolarimetric Fluctuations in a Sunspot Chro…

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We describe the presence of wavefront dislocations in magnetohydrodynamic waves in stratified stellar atmospheres. Scalar dislocations such as edges and vortices can appear in Alfv\'en waves, as well as in general magneto-acoustic waves. We…

Solar and Stellar Astrophysics · Physics 2015-06-16 A. López Ariste , M. Collados , E. Khomenko

The Inverse First Ionization Potential (FIP) Effect, the depletion in coronal abundance of elements like Fe, Mg, and Si that are ionized in the solar chromosphere relative to those that are neutral, has been identified in several solar…

Solar and Stellar Astrophysics · Physics 2021-03-17 J. Martin Laming

We investigate the properties and relationship between Doppler-velocity fluctuations and intensity fluctuations in the off-limb quiet Sun corona. These are expected to reflect the properties of Alfvenic and compressive waves, respectively.…

Solar and Stellar Astrophysics · Physics 2025-03-21 Michael Hahn , Xiangrong Fu , Stefan J. Hofmeister , Yifan Huang , Alexandros Koukras , Daniel Wolf Savin

We investigate non-ideal magnetohydrodynamical (MHD) effects in the chromosphere on the solar wind by performing MHD simulations for Alfv\'en-wave driven winds with explicitly including Ohmic and ambipolar diffusion. We find that MHD waves…

Solar and Stellar Astrophysics · Physics 2024-05-09 Masato Matsuoka , Takeru K. Suzuki , Takato Tokuno , Kensuke Kakiuchi

We investigate possible links between the large-scale and small-scale features of solar wind fluctuations across the frequency break separating fluid and kinetic regimes. The aim is to correlate the magnetic field fluctuations polarization…

Space Physics · Physics 2017-01-26 D. Telloni , R. Bruno

We investigate the propagation of Alfv\'en waves in the solar chromosphere, distinguishing between upward and downward propagating waves. We find clear evidence for the reflection of waves in the chromosphere and differences in propagation…

Parker Solar Probe (PSP) observed sub-Alfvenic solar wind intervals during encounters 8 - 14, and low-frequency magnetohydrodynamic turbulence in these regions may differ from that in super-Alfvenic wind. We apply a new mode-decomposition…

We make use of the Parker Solar Probe (PSP) data to explore the nature of solar wind turbulence focusing on the Alfv\'enic character and power spectra of the fluctuations and their dependence on distance and context (i.e. large scale solar…

We discuss properties of large amplitude magnetic field fluctuations during fast Alfvenic solar wind streams, focussing on the statistics of the rotation angle between consecutive magnetic field vector measurements for different scales in…

Space Physics · Physics 2019-10-17 L. Matteini , D. Stansby , T. S. Horbury , C. H. K. Chen

Measurements and simulations of inertial compressive turbulence in the solar wind are characterized by anti-correlated magnetic fluctuations parallel to the mean field and density structures. This signature has been interpreted as…

Space Physics · Physics 2018-03-14 Trevor A. Bowen , Samuel Badman , Petr Hellinger , Stuart D. Bale

Context. Magnetic bright points (MBPs) are one of the smallest manifestations of the magnetic field in the solar atmosphere and are observed to extend from the photosphere up to the chromosphere. As such, they represent an excellent feature…

Solar and Stellar Astrophysics · Physics 2024-09-19 Arthur Berberyan , Peter H. Keys , David B. Jess , Damian J. Christian

Dissipation of magnetohydrodynamic (MHD) wave energy has been proposed as a viable heating mechanism in the solar chromospheric plasma. Here, we use a simplified one-dimensional model of the chromosphere to theoretically investigate the…

Solar and Stellar Astrophysics · Physics 2015-09-23 Roberto Soler , Marc Carbonell , Jose Luis Ballester

Several studies have reported magnetic field fluctuations associated with umbral shock waves. We aim to study the properties and origin of magnetic field fluctuations in the umbral chromosphere. Temporal series of spectropolarimetric…

Solar and Stellar Astrophysics · Physics 2023-08-09 T. Felipe , S. J. González Manrique , C. R. Sangeetha , A. Asensio Ramos

We discuss properties of Alfv\'enic fluctuations with large amplitude in plasmas characterised by low magnetic field compression. We note that in such systems power laws can not develop with arbitrarily steep slopes at large scales, i.e.…

Space Physics · Physics 2018-12-26 Lorenzo Matteini , David Stansby , Timothy Horbury , Christopher H. K. Chen

The solar atmosphere is known to be replete with magneto-hydrodynamic wave modes, and there has been significant investment in understanding how these waves propagate through the Sun's atmopshere and deposit their energy into the plasma.…

Solar and Stellar Astrophysics · Physics 2023-02-14 R. J. Morton , R. Sharma , E. Tajfirouze , H. Miriyala

Characterizing compressible fluctuations in the solar wind is essential for understanding their role in solar wind acceleration and heating, yet their origin and evolution across different turbulence regimes remain poorly understood. In…

Plasma Physics · Physics 2026-04-13 C. A. Gonzalez , C. Gonzalez , A. Tenerani

We find that the element abundances in solar energetic particles (SEPs) and in the slow solar wind (SSW), relative to those in the photosphere, show different patterns as a function of the first ionization potential (FIP) of the elements.…

Solar and Stellar Astrophysics · Physics 2018-03-13 Donald V. Reames

Bright points (BPs) in the solar photosphere are radiative signatures of magnetic elements described by slender flux tubes located in the darker intergranular lanes. They contribute to the ultraviolet (UV) flux variations over the solar…

Solar and Stellar Astrophysics · Physics 2016-08-11 T. L. Riethmüller , S. K. Solanki , S. V. Berdyugina , M. Schüssler , V. Martínez Pillet , A. Feller , A. Gandorfer , J. Hirzberger

We present observational evidence for the presence of MHD waves in the solar photosphere deduced from SOHO/MDI Dopplergram velocity observations. The magneto-acoustic perturbations are observed as acoustic power enhancement in the sunspot…

Solar and Stellar Astrophysics · Physics 2013-07-10 S. Zharkov , S. Shelyag , V. Fedun , R. Erdélyi , M. J. Thompson

Two of the central problems in our understanding of the solar chromosphere are how the upper chromosphere is heated and what drives spicules. Estimates of the required chromospheric heating, based on radiative and conductive losses suggest…

Solar and Stellar Astrophysics · Physics 2016-10-05 C. S. Brady , T. D. Arber