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Related papers: Solar flares and Kelvin-Helmholtz instabilities: A…

200 papers

Electron-scale Kelvin-Helmholtz instabilities (ESKHI) are found in several astrophysical scenarios. Naturally ESKHI is subject to a background magnetic field, but an analytical dispersion relation and an accurate growth rate of ESKHI under…

Plasma Physics · Physics 2025-02-25 Yao Guo , Dong Wu , Jie Zhang

We study flare processes in the solar atmosphere using observational data for a M1-class flare of June 12, 2014, obtained by New Solar Telescope (NST/BBSO) and Helioseismic Magnetic Imager (HMI/SDO). The main goal is to understand triggers…

Solar and Stellar Astrophysics · Physics 2018-01-17 I. N. Sharykin , V. M. Sadykov , A. G. Kosovichev , S. Vargas-Dominguez , I. V. Zimovets

We explore the temporal relationship between microwave/HXR emission and Doppler velocity during the impulsive phase of a solar flare on 2014 October 27 (SOL2014-10-27), which displays a pulse on the light curves in microwave (34 GHz) and…

Solar and Stellar Astrophysics · Physics 2017-05-24 Dong Li , Zongjun Ning , Yu Huang , Qingmin Zhang

The physics of solar flares occurring on the Sun is highly complex and far from fully understood. However, observations show that solar eruptions are associated with the intense kilogauss fields of active regions, where free energies are…

Solar and Stellar Astrophysics · Physics 2024-01-26 Bach Viet Do , Yang Chen , XuanLong Nguyen , Ward Manchester

The X2.2-class solar flare of February 15, 2011, produced a powerful `sunquake' event, representing a seismic response to the flare impact. The impulsively excited seismic waves formed a compact wavepacket traveling through the solar…

Solar and Stellar Astrophysics · Physics 2011-02-22 A. G. Kosovichev

Helioseismic data from the HMI instrument have revealed a sunquake associated with the X1 flare SOL2014-03-29T17:48 in active region NOAA 12017. We try to discover if acoustic-like impulses or actions of the Lorentz force caused the…

Solar and Stellar Astrophysics · Physics 2015-06-22 Philip G. Judge , Lucia Kleint , Alina Donea , Alberto Sainz Dalda , Lyndsay Fletcher

We model an imaged Kelvin-Helmholtz (KH) instability on a coronal mass ejecta (CME) in the lower corona by investigating conditions under which kink ($m = 1$) and $m = -3$ magnetohydrodynamic (MHD) modes in an uniformly twisted flux tube…

Solar and Stellar Astrophysics · Physics 2015-01-28 I. Zhelyazkov , T. V. Zaqarashvili , R. Chandra

We study flare processes in the lower solar atmosphere using observational data for a M1-class flare of June 12, 2014, obtained by New Solar Telescope (NST/BBSO) and Helioseismic Magnetic Imager (HMI/SDO). The main goal is to understand…

Solar and Stellar Astrophysics · Physics 2016-04-20 I. N. Sharykin , V. M. Sadykov , A. G. Kosovichev , S. Vargas-Dominguez , I. V. Zimovets

The fluid behavior of the solar wind is affected by the heat flux carried by the suprathermal electron populations, especially the electron strahl (or beam) that propagates along the magnetic field. In turn, the electron strahl cannot be…

Plasma Physics · Physics 2025-07-08 Dustin L. Schröder , Marian Lazar , Rodrigo A. López , Horst Fichtner

Solar flares emanate from solar active regions hosting complex and strong bipolar magnetic fluxes. Estimating the probability of an active region to flare and defining reliable precursors of intense flares is an extremely challenging task…

Solar hard X-rays (HXRs) appear in the form of either footpoint sources or coronal sources, and each individual source provides its own critical information on acceleration of nonthermal electrons and plasma heating. Earlier studies found…

Solar and Stellar Astrophysics · Physics 2019-06-11 Hao Ning , Yao Chen , Jeongwoo Lee , Zhao Wu , Yang Su , Xiang-Liang Kong

In solar flares, inverse Compton scattering (ICS) of photospheric photons might give rise to detectable hard X-ray photon fluxes from the corona where ambient densities are too low for significant bremsstrahlung or recombination. Gamma-ray…

Solar and Stellar Astrophysics · Physics 2015-05-14 Alec L. MacKinnon , Procheta C. V. Mallik

This study presents three-dimensional (3D) resistive Hall-magnetohydrodynamic simulations of the Kelvin-Helmholtz instability (KHI) dynamics at Earth's magnetospheric flanks during northward interplanetary magnetic field periods. By…

Space Physics · Physics 2024-05-24 Silvia Ferro , Matteo Faganello , Francesco Califano , Fabio Bacchini

We conduct a detailed analysis of an M1.3 limb flare occurring on 2017 July 3, which have the X-ray observations recorded by multiple hard X-ray telescopes, including Hard X-ray Modulation Telescope (Insight-HXMT), Ramaty High Energy Solar…

High Energy Astrophysical Phenomena · Physics 2022-05-04 Ping Zhang , Wei Wang , Yang Su , Shuangnan Zhang , Liming Song , Fangjun Lu , Shu Zhang

We present a comprehensive study of Magnetospheric Multiscale (MMS) spacecraft encounter with KHI during a geomagnetic storm, focusing on elucidating key turbulence properties and reconnection signatures observed at the edges of KH…

We study synchrotron self-inverse Compton radiation from a reverse-shocked fireball. If the inverse Compton process dominates the cooling of shocked electrons, an X-ray flare produced by the first order Compton scattering would emerge in…

Astrophysics · Physics 2008-11-26 Shiho Kobayashi , Bing Zhang , Peter Meszaros , David N. Burrows

Models fail to reproduce observations of the coldest parts of the Sun's atmosphere, where interactions between multiple ionized and neutral species prevent an accurate MHD representation. This paper argues that a meter-scale electrostatic…

Solar and Stellar Astrophysics · Physics 2023-06-07 Samuel Evans , Meers Oppenheim , Juan Martínez-Sykora , Yakov Dimant , Richard Xiao

The purpose of this study is to analyze the dynamical role of a radiation field on the growth rate of the unstable Kelvin - Helmholtz (KH) perturbations. As a first step toward this purpose, the analyze is done in a general way,…

Astrophysics of Galaxies · Physics 2015-06-04 Mohsen Shadmehri , Zahra Enayati , Mahdi Khajavi

Solar flares show highly unusual spectra, in which the thermodynamic conditions of the solar atmosphere are encoded. Current models are unable to fully reproduce the spectroscopic flare observations, especially the single-peaked spectral…

Solar and Stellar Astrophysics · Physics 2017-06-28 Fatima Rubio da Costa , Lucia Kleint

Recent numerical studies of oscillating flux tubes have established the significance of resonant absorption in the damping of propagating transverse oscillations in coronal loops. The nonlinear nature of the mechanism has been examined…

Solar and Stellar Astrophysics · Physics 2017-08-30 K. Karampelas , T. Van Doorsselaere , P. Antolin