Results 31 to 40 of about 429,936 (298)

DEM Study of Selected Quiet Sun Regions [PDF]

Symposium - International Astronomical Union, 2001
In the present work EUV spectra of quiet Sun regions, observed with the Coronal Diagnostic Spectrometer (CDS) on SOHO, are analysed in order to determine the Differential Emission Measure (DEM) of selected areas of the field of view. The purpose of the present work is to study the differences between the DEM curves of the quiet Sun cell centers areas ...
Gontikakis, C., Landi, E., Dara, H. C., Alissandrakis, C. E., Vial, J. C.   +4 more
openaire   +2 more sources

Propagating and Stationary Bright Knots in the Quiet Sun

The Astrophysical Journal Letters, 2022
The question of what heats the solar chromosphere and corona remains one of the most important puzzles in solar physics and astrophysics. Up to now, two mechanisms are considered to work in heating the chromosphere and corona: magnetic reconnection and ...
Jun Zhang, Yijun Hou, Yue Fang, Feng Chen, Ting Li, Xiaoli Yan, Tao Ding, Zhiping Song, Yongyuan Xiang, Zhong Liu   +9 more
doaj   +1 more source

On the Magnetic Nature of Quiet-Sun Chromospheric Grains

The Astrophysical Journal Letters, 2023
Ca ii K grains, i.e., intermittent, short-lived (about 1 minute), periodic (2–4 minutes), pointlike chromospheric brightenings, are considered to be the manifestations of acoustic waves propagating upward from the solar surface and developing into shocks
María Jesús Martínez González, Tanausú del Pino Alemán, Adur Pastor Yabar, C. Quintero Noda, Andrés Asensio Ramos   +4 more
doaj   +1 more source

Energy and helicity budgets of solar quiet regions

, 2014
We investigate the free magnetic energy and relative magnetic helicity budgets of solar quiet regions. Using a novel non-linear force-free method requiring single solar vector magnetograms we calculate the instantaneous free magnetic energy and relative ...
Georgoulis, M. K., Kontogiannis, I., Tsiropoula, G., Tziotziou, K.   +3 more
core   +1 more source

The dark side of solar photospheric G-band bright points

, 2016
Bright small-scale magnetic elements found mainly in intergranular lanes at the solar surface are named bright points (BPs). They show high contrasts in Fraunhofer G-band observations and are described by nearly vertical slender flux tubes or sheets.
Riethmüller, T. L., Solanki, S. K.
core   +1 more source

Chromosphere of the quiet sun

Astronomy & Astrophysics
Context. The solar chromosphere is a dynamic and crucial interface between the solar interior and its interplanetary environment, regulating how energy is locally deposited into heat and transported into the upper atmospheric layers.
Noraz Q., Carlsson M., Aulanier G.
doaj   +1 more source

Is the Polar Region Different from the Quiet Region of the Sun?

, 2010
Observations of the polar region of the Sun are critically important for understanding the solar dynamo and the acceleration of solar wind. We carried out precise magnetic observations on both the North polar region and the quiet Sun at the East limb ...
Bellot Rubio, Daikou Shiota, Fujimura, Hiroaki Ito, Ishikawa, Kamio, Kano, Ken'ichi Fujiki, Lites, Lites, Munetoshi Tokumaru, Orozco Suárez, Orozco Suárez, Saku Tsuneta, Savcheva, Severny, Shimojo, Tsuneta   +17 more
core   +1 more source

Bright Points in the Internetwork Quiet Sun

The Astrophysical Journal, 2004
High resolution G-band images of the interior of a supergranulation cell show ubiquitous Bright Points (some 0.3 BPs per Mm^2). They are located in intergranular lanes and often form chains of elongated blobs whose smallest dimension is at the resolution limit (135 km on the Sun). Most of them live for a few minutes, having peak intensities from 0.8 to
Almeida, J. S., Marquez, I., Bonet, J. A., Cerdena, I. D., Mueller, R.   +4 more
openaire   +3 more sources

Magnetic properties of photospheric regions having very low magnetic flux

, 2001
The magnetic properties of the quiet Sun are investigated using a novel inversion code, FATIMA, based on the Principal Component Analysis of the observed Stokes profiles.
Bianda M., Bianda M., Grossmann-Doerth U., H. Socas‐Navarro, J. Sanchez Almeida, Keller C., Kneer F., Livingston W., Rees D., Sigwarth M., Smithson R., Stenflo J., Stenflo J., Zhang J.   +13 more
core   +1 more source

A nanoflare model of quiet Sun EUV emission [PDF]

, 2006
Nanoflares have been proposed as the main source of heating of the solar corona. However, detecting them directly has so far proved elusive, and extrapolating to them from the properties of larger brightenings gives unreliable estimates of the power-law ...
A. Pauluhn, Arzner, Aschwanden, Aschwanden, Audard, Brkovic, Datlowe, Güdel, Harrison, Innes, Krucker, Lin, Lu, Mitra-Kraev, Parker, Parnell, Pauluhn, Rosner, S. K. Solanki, Torrence, Vekstein, Wilhelm, Wilhelm, Winebarger, Withbroe   +24 more
core   +2 more sources