Results 1 to 10 of about 368 (163)

Understanding the heating mechanism of the solar active region atmosphere in chromosphere

Journal of Physics: Conference Series, 2023
Abstract Understanding the mechanisms underlying the heating of the solar atmosphere is a fundamental problem in solar physics. In this paper, we present an overview of our research on understanding the heating mechanism of the solar active region atmosphere in chromosphere. We investigate Joule heating due to the dissipation of currents
M S Yalım, C Beck, Debi Prasad Choudhary   +2 more
exaly   +4 more sources

An overall view of temperature oscillations in the solar chromosphere with ALMA. [PDF]

Philos Trans A Math Phys Eng Sci, 2021
Jafarzadeh S, Wedemeyer S, Fleck B, Stangalini M, Jess DB, Morton RJ, Szydlarski M, Henriques VMJ, Zhu X, Wiegelmann T, Guevara Gómez JC, Grant SDT, Chen B, Reardon K, White SM.   +14 more
europepmc   +2 more sources

NANOFLARE ACTIVITY IN THE SOLAR CHROMOSPHERE [PDF]

The Astrophysical Journal, 2014
We use ground-based images of high spatial and temporal resolution to search for evidence of nanoflare activity in the solar chromosphere. Through close examination of more than 10^9 pixels in the immediate vicinity of an active region, we show that the distributions of observed intensity fluctuations have subtle asymmetries.
Jess, D. B., Mathioudakis, M., Keys, P. H.   +2 more
openaire   +3 more sources

On the Connection between Rieger-type and Magneto-Rossby Waves Driving the Frequency of the Large Solar Eruptions during Solar Cycles 19–25

The Astrophysical Journal, 2023
Global solar activity variation mainly occurs over about an 11 yr cycle. However, both longer and shorter periodicities than the solar cycle are also present in many different solar activity indices.
Marianna B. Korsós, Mausumi Dikpati, Robertus Erdélyi, Jiajia Liu, Francesca Zuccarello   +4 more
doaj   +1 more source

Chromospheric structure and activity in solar analogues [PDF]

Proceedings of the International Astronomical Union, 2004
We computed chromospheric models of the Sun as a star and of nine solar analogues. The stars have a wide variety of magnetic activity levels, which allows us to study the differences in atmospheric structures induced by activity.To search for other articles by the author(s) go to: http://adsabs.harvard.edu/abstract_service ...
M. C. Vieytes, P. J. D. Mauas, C. C. Cincunegui   +2 more
openaire   +1 more source

Alfvén Wave Connection between the Chromosphere and the Corona of the Sun: An Analytical Study

The Astrophysical Journal, 2023
Alfvén waves are closely relevant to the three outstanding problems in the solar corona: coronal heating, solar wind acceleration, and the fractionization of low first ionization potential (FIP) elements.
Jongchul Chae, Kyoung-Sun Lee
doaj   +1 more source

Chromospheric models of solar analogues with different activity levels [PDF]

Astronomy & Astrophysics, 2005
We computed chromospheric models of the Sun as a star and of nine solar analogues. The atmospheric models were constructed to obtain the best possible match with the Ca II K and Hβ lines, including the asymmetry of the lines due to macroscopic velocity fields.
Vieytes, Mariela Cristina, Mauas, Pablo Jacobo David, Cincunegui, Carolina Cecilia   +2 more
openaire   +2 more sources

An ALMA Observation of Time Variations in Chromospheric Temperature of a Solar Plage Region

Frontiers in Astronomy and Space Sciences, 2022
Nanoflares and the shock formation of magnetohydrodynamic waves in the solar chromosphere have been considered as key physical mechanisms of the heating of the chromosphere and corona.
Masashi Abe, Masashi Abe, Toshifumi Shimizu, Toshifumi Shimizu, Masumi Shimojo, Masumi Shimojo   +5 more
doaj   +1 more source

First Observation of Chromospheric Waves in a Sunspot by DKIST/ViSP: The Anatomy of an Umbral Flash

The Astrophysical Journal Letters, 2023
The Visible Spectro-Polarimeter of the NSF Daniel K. Inouye Solar Telescope collected its Science Verification data on 2021 May 7–8. The instrument observed multiple layers of a sunspot atmosphere simultaneously, in passbands of Ca ii 397 nm (H line), Fe
Ryan J. French, Thomas J. Bogdan, Roberto Casini, Alfred G. de Wijn, Philip G. Judge   +4 more
doaj   +1 more source

Chromosphere Activity Relation with Solar Dynamo Magnetic Activity Cycle

Iranian Journal of Astronomy and Astrophysics, 2022
In this article, we analyzed the abnormal thickness of the chromosphere above the coronal holes (CH) at the poles of the Sun for 13 years (2010-2022), on the 15th of every month, by using AIA/SDO telescope data. We used the light emitted from helium-2 (He II) at a wavelength of 304 {AA} at about 50,000 K to investigate the solar holes in its north and ...
Tavabi, Ehsan, Rajabi, Mina, Zeighami, Sima   +2 more
openaire   +2 more sources