Results 41 to 50 of about 1,105,860 (262)
Ion–neutral Interactions and Nonequilibrium Ionization in the Solar Chromosphere [PDF]
Astrophysical Journal, 2019 The thermal structure of the chromosphere is regulated through a complex interaction of various heating processes, radiative cooling, and the ionization degree of the plasma.
J. Martínez-Sykora +6 more
semanticscholar +1 more source
MAGNETIC DIAGNOSTICS OF THE SOLAR CHROMOSPHERE WITH THE Mg II h–k LINES [PDF]
, 2016 We investigated the formation of the Mg ii h–k doublet in a weakly magnetized atmosphere (20–100 G) using a newly developed numerical code for polarized radiative transfer in a plane-parallel geometry, which implements a recent formulation of partially ...
Tanausú del Pino Alemán +2 more
openalex +3 more sources
Newly Discovered Source of Turbulence and Heating in the Solar Chromosphere
Astrophysical Journal, 2020 Above the Sun’s luminous photosphere lies the solar chromosphere, where the temperature increases from below 4000 K to over 1 million K. Though physicists do not understand the origin of these increases, they know it powers the solar wind with enormous ...
M. Oppenheim +3 more
semanticscholar +1 more source
Heating of a Quiet Region of the Solar Chromosphere by Ion and Neutral Acoustic Waves [PDF]
Astrophysical Journal, 2019 Using high-resolution numerical simulations we investigate the plasma heating driven by periodic two-fluid acoustic waves that originate at the bottom of the photosphere and propagate into the gravitationally stratified and partially ionized solar ...
B. Ku'zma, D. W'ojcik, K. Murawski
semanticscholar +1 more source
The Astrophysical Journal Letters, 2023 The heating of the chromosphere in internetwork regions remains one of the foremost open questions in solar physics. In the present study, we tackle this old problem by using a very-high-spatial-resolution simulation of quiet-Sun conditions performed ...
Juan Martínez-Sykora +5 more
doaj +1 more source
ALMA Observations of the Solar Chromosphere on the Polar Limb [PDF]
Astrophysical Journal, 2018 We report the results of the Atacama Large Millimeter/sub-millimeter Array (ALMA) observations of the solar chromosphere on the southern polar limb. Coordinated observations with the Interface Region Imaging Spectrograph (IRIS) are also conducted.
T. Yokoyama +3 more
semanticscholar +1 more source
On the Origin of the Magnetic Energy in the Quiet Solar Chromosphere [PDF]
Astrophysical Journal, 2019 The presence of magnetic field is crucial in the transport of energy through the solar atmosphere. Recent ground-based and space-borne observations of the quiet Sun have revealed that magnetic field accumulates at photospheric heights, via a local dynamo
J. Martínez-Sykora +5 more
semanticscholar +1 more source
The Astrophysical Journal, 2023 The ponderomotive force has been suggested to be the main mechanism to produce the so-called first ionization potential (FIP) effect—the enrichment of low-FIP elements observed in the outer solar atmosphere, in the solar wind, and in solar energetic ...
Juan Martínez-Sykora +5 more
doaj +1 more source
The Magnetic Sensitivity of the (250–278 nm) Fe ii Polarization Spectrum
The Astrophysical Journal, 2023 This paper presents a theoretical investigation of the polarization and magnetic sensitivity of the near-ultraviolet (near-UV) solar spectral lines of Fe ii between 250 and 278 nm.
David Afonso Delgado +2 more
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Element Abundances in Impulsive Solar Energetic Particle Events
The Astrophysical Journal, 2023 We outline and discuss a model for the enhanced abundances of trans-Fe elements in impulsive solar energetic particle (SEP) events, where large mass-dependent abundance enhancements are frequently seen.
J. Martin Laming, Natsuha Kuroda
doaj +1 more source