Results 81 to 90 of about 8,745 (214)

Deconstructing Photospheric Spectral Lines in Solar and Stellar Flares

The Astrophysical Journal
During solar flares, spectral lines formed in the photosphere have been shown to exhibit changes to their profiles despite the challenges of energy transfer to these depths.
Aaron J. Monson, Mihalis Mathioudakis, Adam F. Kowalski   +2 more
doaj   +1 more source

Transient rotation of photospheric vector magnetic fields associated with a solar flare

Nature Communications, 2018
The violent solar eruptions known as flares are caused by magnetic reconnection. Here, the authors identify a sudden 12°–20° counter clockwise rotation of vector magnetic fields in photosphere, associated with the emissions of moving flare ribbons.
Yan Xu, Wenda Cao, Kwangsu Ahn, Ju Jing, Chang Liu, Jongchul Chae, Nengyi Huang, Na Deng, Dale E. Gary, Haimin Wang   +9 more
doaj   +1 more source

Multi-height probing of horizontal flows in the solar photosphere

Astronomy & Astrophysics
Context. Optical flow methods aim to infer horizontal (transverse, in the general case) velocities in the solar atmosphere from the temporal changes in maps of physical quantities, such as intensity or magnetic field.
Kostić T., Milić I., Rempel M., Welsch B., Kazachenko M., Asensio Ramos A., Tremblay B.   +6 more
doaj   +1 more source

The operation of the Williamson Photosphere

, 1915
Photograph of artist sketch showing the operation of the Williamson Photosphere, drawn by Williamson in 1915.https://digitalcommons.chapman.edu/jonathan_silent_film/2164/thumbnail ...

core   +1 more source

Neutrino Constraints and Detection Prospects from Gamma-Ray Bursts with Different Jet Compositions

The Astrophysical Journal
The prompt emission mechanism of gamma-ray bursts (GRBs) is a long-standing open question, and GRBs have been considered as potential sources of high-energy neutrinos. Despite many years of search for the neutrino events associated with GRBs from IceCube,
Yang-Dong-Jun Ou, Hou-Jun Lü, Xue-Zhao Chang, Xiao-Xuan Liu, En-Wei Liang   +4 more
doaj   +1 more source

Chromospheric and photospheric properties of sunspots as inferred from Stokes inversions under magnetohydrostatic and non-local thermodynamic equilibrium

Astronomy & Astrophysics
Context. Sunspots represent a key feature in the solar atmosphere to explore how magnetic fields interact with plasma flows, exhibiting large variations in physical parameters over very small spatial scales (< 100 km), and sometimes featuring dynamic ...
Vicente Arévalo A., Borrero J. M., Milić I., Pastor Yabar A., Kontogiannis I., Pietrow A. G. M.   +5 more
doaj   +1 more source

Magnetic Flux Emergence and Solar Eruptions in Partially Ionized Plasmas

The Astrophysical Journal
We have performed 3D MHD simulations to study the effect of partial ionization in the process of magnetic flux emergence in the Sun. In fact, we continue previous work, and we now focus (1) on the emergence of the magnetic fields above the solar ...
Georgios Chouliaras, V. Archontis
doaj   +1 more source

Assessment of DKIST/VTF capabilities for the detection of local acoustic source wavefronts

Frontiers in Astronomy and Space Sciences
IntroductionRecent studies have demonstrated that temporal filtering can successfully identify local acoustic source wavefronts in radiative magnetohydrodynamic simulations of the solar photosphere.
Corinne Morrell, Corinne Morrell, Mark P. Rast, Mark P. Rast, Shah Mohammad Bahauddin, Shah Mohammad Bahauddin, Ivan Milić   +6 more
doaj   +1 more source

Hawking radiation photosphere around microscopic black holes

, 1998
The Boltzmann equation for the diffusion of Hawking radiation from microscopic black holes is solved using the test particle method. Formation of a dense cloud of interacting particles analogous to the photosphere of the Sun is confirmed. We find that at
Mostoslavsky, Michael.
core  

Formation of a Magnetic Flux Rope prior to the Eruption: Insight from a Radiative MHD Simulation of Active Region Emergence

The Astrophysical Journal Letters
Magnetic flux ropes are fundamental magnetic structures in solar eruptions, whose formation is generally attributed to: (1) the emergence of subsurface flux tubes; or (2) flux cancellation driven by photospheric horizontal flows and magnetic reconnection.
Can Wang, Takaaki Yokoyama, Feng Chen, Chen Xing, Mingde Ding, Zekun Lu   +5 more
doaj   +1 more source