Results 11 to 20 of about 332 (133)
Inference of chromospheric plasma parameters on the Sun [PDF]
Astronomy & Astrophysics, 2020 The solar chromosphere can be observed well through strong absorption lines. We infer the physical parameters of chromospheric plasmas from these lines using a multilayer spectral inversion. This is a new technique of spectral inversion. We assume that the atmosphere consists of a finite number of layers.
Chae, Jongchul +3 more
openaire +3 more sources
Properties of shock waves in the quiet-Sun chromosphere
Astronomy & Astrophysics, 2022 Context.Short-lived (100 s or less), sub-arcsec to a couple of arcsec sized features of enhanced brightenings in the narrowband images at the H2Vand K2Vpositions of the Ca IIH&K lines in the quiet Sun are known as bright grains. These bright grains are interpreted as manifestations of acoustic shock waves in the chromosphere.Aims.We aim to study ...
Harsh Mathur +4 more
openaire +3 more sources
Observations of ubiquitous compressive waves in the Sun’s chromosphere [PDF]
Nature Communications, 2012 The details of the mechanism(s) responsible for the observed heating and dynamics of the solar atmosphere still remain a mystery. Magnetohydrodynamic (MHD) waves are thought to play a vital role in this process. Although it has been shown that incompressible waves are ubiquitous in off-limb solar atmospheric observations their energy cannot be readily ...
Morton, R.J. +6 more
openaire +5 more sources
CHROMOSPHERIC MAGNETIC RECONNECTION ON THE SUN [PDF]
Journal of The Korean Astronomical Society, 2002 Solar observations support that magnetic reconnect ion ubiquitously occurs in the chromosphere as well as in the corona. It is now widely accepted that coronal magnetic reconnect ion is fast reconnect ion of the Petschek type, and is the main driver of solar flares.
JONGCHUL CHAE +2 more
openaire +1 more source
Chromospheric Cannonballs on the Sun
The Astrophysical Journal Letters, 2019 Abstract In the highly dynamic chromosphere, there exist many kinds of small-scale activities, such as spicules, surges, and Ellerman bombs. Here, we report the discovery of a new phenomenon in the chromosphere observed with the New Vacuum Solar Telescope at the Fuxian Solar Observatory.
Shuhong Yang +4 more
openaire +2 more sources
Processes in the magnetized chromosphere of the Sun [PDF]
Proceedings of the International Astronomical Union, 2008 AbstractWe review physical processes in magnetized chromospheres on the Sun. In the quiet chromosphere, it is useful to distinguish between the magnetic network on the boundaries of supergranules, where strong magnetic fields are organized in mainly vertical flux tubes and internetwork regions in the cell interiors, which have traditionally been ...
openaire +1 more source
ALMA Detection of Dark Chromospheric Holes in the Quiet Sun [PDF]
The Astrophysical Journal Letters, 2019 Abstract We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of a quiet-Sun region at a wavelength of 3 mm, obtained during the first solar ALMA cycle on 2017 April 27, and compare them with available chromospheric observations in the UV and visible as well as with photospheric magnetograms.
Maria A. Loukitcheva +2 more
openaire +3 more sources
ON THE MISALIGNMENT BETWEEN CHROMOSPHERIC FEATURES AND THE MAGNETIC FIELD ON THE SUN [PDF]
The Astrophysical Journal Letters, 2016 ABSTRACT Observations of the upper chromosphere show an enormous amount of intricate fine structure. Much of this comes in the form of linear features, which are most often assumed to be well aligned with the direction of the magnetic field in the low plasma β regime that is thought to dominate the upper chromosphere.
Juan Martínez-Sykora +3 more
openaire +2 more sources
Basal chromospheric flux and Maunder Minimum-type stars: the quiet-Sun chromosphere as a universal phenomenon [PDF]
Astronomy & Astrophysics, 2012 Aims: We demonstrate the universal character of the quiet-Sun chromosphere among inactive stars (solar-type and giants). By assessing the main physical processes, we shed new light on some common observational phenomena. Methods: We discuss measurements of the solar Mt.
Schroeder, K. -P. +4 more
openaire +2 more sources
Ultraviolet Oscillations in the Chromosphere of the Quiet Sun
The Astrophysical Journal, 2004 Quiet-Sun oscillations in the four Transition Region and Coronal Explorer (TRACE) ultraviolet passbands centered on 1700, 1600, 1216, and 1550 A are studied using a wavelet-based technique. Both network and internetwork regions show oscillations with a variety of periods and lifetimes in all passbands. The most frequent network oscillation has a period
Keenan, Francis +5 more
openaire +1 more source