Zobrazeno 1 - 10
of 76
pro vyhledávání: '"Solar Ultraviolet Emission"'
Publikováno v:
The Astrophysical Journal Letters, Vol 970, Iss 1, p L16 (2024)
The variability of helium abundance in the solar corona and the solar wind is an important signature of solar activity, solar cycle, and solar wind sources, as well as coronal heating processes. Motivated by recently reported remote-sensing UV imagin
Externí odkaz:
https://doaj.org/article/0c7c5914d62d49ebb8a16504cc9e09f2
Autor:
Shuting Li, Li Feng, Beili Ying, Lei Lu, Kaifan Ji, Ying Li, Guanglu Shi, Hui Li, Yu Huang, Weiqun Gan
Publikováno v:
The Astrophysical Journal Letters, Vol 969, Iss 1, p L16 (2024)
H i Ly α emission in the chromosphere and transition region is a key ingredient of the incident radiation to coronal neutral hydrogen for modeling corona Ly α emission. The Ly α emission distribution across the solar disk can be obtained from a Ly
Externí odkaz:
https://doaj.org/article/26f625d8043e4bd4a47f92f3806d311b
Autor:
Sarah A. Jaeggli, Adrian N. Daw
Publikováno v:
The Astrophysical Journal, Vol 976, Iss 1, p 18 (2024)
A rich spectrum of molecular hydrogen (H _2 ) emission lines is seen in sensitive observations from the far-ultraviolet (FUV) channels of the Interface Region Imaging Spectrograph (IRIS) during flare activity in solar active region NOAA Active Region
Externí odkaz:
https://doaj.org/article/1c3756d952e24fcfa2ae1df4e95b8af2
Publikováno v:
The Astrophysical Journal, Vol 975, Iss 1, p 33 (2024)
The origin of nonthermal broadening in solar spectra is one of the long-standing questions in solar physics. Various processes have been invoked—including unresolved flows, waves, and turbulent processes—but definitive answers are lacking. To inv
Externí odkaz:
https://doaj.org/article/c293ff8bc753426e907fc2dd2bec0cc5
Autor:
R. P. Dufresne, G. Del Zanna, P. R. Young, K. P. Dere, E. Deliporanidou, W. T. Barnes, E. Landi
Publikováno v:
The Astrophysical Journal, Vol 974, Iss 1, p 71 (2024)
Version 11 of the chianti database and software package is presented. Advanced ionization equilibrium models have been added for low charge states of seven elements (C, N, O, Ne, Mg, Si, and S), and represent a significant improvement especially when
Externí odkaz:
https://doaj.org/article/42feac35a1924fa18390f7eaac86e441
Publikováno v:
The Astrophysical Journal, Vol 973, Iss 1, p 57 (2024)
Coronal rain (CR) is a crucial part of the mass cycle between the corona and chromosphere. It includes flare-driven CR and two types of quiescent CR, along nonflaring active region closed loops and along open structures, separately, labeled as type I
Externí odkaz:
https://doaj.org/article/9f4b1644ba194ed0949881d46145719d
Publikováno v:
The Astrophysical Journal, Vol 970, Iss 1, p 77 (2024)
We report the simultaneous observations of quasiperiodic pulsations (QPPs) in wavelengths of hard X-ray (HXR), microwave, Ly α , and ultraviolet (UV) emissions during the impulsive phase of an X6.4 flare on 2024 February 22 (SOL2024-02-22T22:08). Th
Externí odkaz:
https://doaj.org/article/1995912f98604bd98f33cd1ed6125c83
Autor:
Elizabeth C. Butler, Adam F. Kowalski
Publikováno v:
The Astrophysical Journal, Vol 970, Iss 1, p 33 (2024)
Chromospheric condensations (CCs) are a prominent feature of flare footpoint heating in the solar flare standard model, yet their timescales and velocities are not well understood. Fisher derived several important analytical relationships, which have
Externí odkaz:
https://doaj.org/article/0b481ab1c1d34d0a996857bc5b95d834
Autor:
Lucas Dyke, Hans-Reinhard Müller
Publikováno v:
The Astrophysical Journal, Vol 968, Iss 2, p 58 (2024)
Radiation pressure exerted by solar photon output is salient to the motion of primary neutral hydrogen atoms streaming into the inner heliosphere directly from the local interstellar medium. The action of a time-dependent radiation pressure force, wh
Externí odkaz:
https://doaj.org/article/e895d389b51c45018828981d0c55b61a
Autor:
Yuchuan Wu, Zhenyong Hou, Wenxian Li, Xianyong Bai, Yongliang Song, Xiao Yang, Ziyao Hu, Yuanyong Deng, Kaifan Ji
Publikováno v:
The Astrophysical Journal, Vol 965, Iss 2, p 109 (2024)
Upflows and downflows at active region (AR) boundaries have been frequently observed with spectroscopic observations at extreme ultraviolet passbands. In this paper, we report the coexistence of upflows and downflows at the AR boundaries with imaging
Externí odkaz:
https://doaj.org/article/deaa8176bb614afd9bd5a6daf2a7515f