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Related papers: Observations of solar chromospheric heating at sub…

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We investigate the thermal properties of a solar flare by the observations of soft X-ray Telescope (XRT) on board Hinode and the Atmospheric Image Assembly on board the Solar Dynamics Observatory (SDO/AIA). Our analysis reveals a tenuous…

Solar and Stellar Astrophysics · Physics 2025-10-22 Xiaoyan Xie , Anna Chen , Crisel Suarez , Katharine K. Reeves , Soumya Roy , Christopher S. Moore , Nishu Karna , Joy Velasquez

The chromosphere is a complex region that acts as an intermediary between the magnetic flux emergence in the photosphere and the magnetic features seen in the corona. Large eruptions in the chromosphere of flares and filaments are often…

Solar and Stellar Astrophysics · Physics 2017-09-20 Michael S. Kirk , K. S. Balasubramaniam , Jason Jackiewicz , Holly R. Gilbert

We analyze and model an M8.0 flare on 2005 May 13 observed by TRACE and RHESSI to determine the energy release rate from magnetic reconnection that forms and heats numerous flare loops. The flare exhibits two ribbons in UV 1600 {\AA}…

Solar and Stellar Astrophysics · Physics 2014-06-25 Wen-Juan Liu , Jiong Qiu , Dana W. Longcope , Amir Caspi

We have performed 3D radiation MHD simulations extending from the convection zone to the corona covering a box 16 Mm$^3$ at 32 km spatial resolution. The simulations show very fine structure in the chromosphere with acoustic shocks…

Solar and Stellar Astrophysics · Physics 2010-01-12 Mats Carlsson , Viggo H. Hansteen , Boris V. Gudiksen

We report on observation of the unusual kind of solar microflares, presumably associated with the so-called "topological trigger" of magnetic reconnection, which was theoretically suggested long time ago by Gorbachev et al. (Sov. Ast. 1988,…

Solar and Stellar Astrophysics · Physics 2017-11-15 Yurii V. Dumin , Boris V. Somov

Spatially-resolved X-ray observations are the key to understanding electron acceleration in solar flares. Currently, the underlying processes that efficiently energize solar flare particles are poorly constrained. Abundant flare…

Solar and Stellar Astrophysics · Physics 2026-03-09 Morgan Stores , Natasha Jeffrey , Ewan Dickson , James McLaughlin , Eduard Kontar

We analyze a confined flare that developed a hot cusp-like structure high in the corona (H ~ 66 Mm). A growing cusp-shaped flare arcade is a typical feature in the standard model of eruptive flares, caused by magnetic reconnection at…

Solar flares signify the sudden release of magnetic energy and are sources of so called space weather. The fine structures (below 500 km) of flares are rarely observed and are accessible to only a few instruments world-wide. Here we present…

Solar and Stellar Astrophysics · Physics 2016-04-29 Ju Jing , Yan Xu , Wenda Cao , Chang Liu , Dale Gary , Haimin Wang

Magnetic reconnection at small spatial scales is a fundamental driver of energy release and plasma dynamics in the lower solar atmosphere. We present observations of a brightening in an active region, captured in high-resolution data from…

Solar and Stellar Astrophysics · Physics 2025-04-14 J. M. da Silva Santos , E. Dunnington , R. Jarolim , S. Danilovic , S. Criscuoli

Context. Photospheric motions shuffle the footpoints of the strong axial magnetic field that threads coronal loops giving rise to turbulent nonlinear dynamics characterized by the continuous formation and dissipation of field-aligned…

Solar and Stellar Astrophysics · Physics 2012-08-14 R. B. Dahlburg , G. Einaudi , A. F. Rappazzo , M. Velli

The chromospheric response to the input of flare energy is marked by extended extreme ultraviolet (EUV) ribbons and hard X-ray (HXR) footpoints. These are usually explained as the result of heating and bremsstrahlung emission from…

Solar and Stellar Astrophysics · Physics 2016-01-20 Paulo J. A. Simões , David R. Graham , Lyndsay Fletcher

Small flares frequently occur in the quiet Sun. Previous studies have noted that they share many common characteristics with typical solar flares in active regions. However, their similarities and differences are not fully understood,…

Solar and Stellar Astrophysics · Physics 2023-05-03 Yuji Kotani , Takako T. Ishii , Daiki Yamasaki , Kenichi Otsuji , Kiyoshi Ichimoto , Ayumi Asai , Kazunari Shibata

This paper presents an overview of some recent observational and theoretical results on solar flares, with an emphasis on flare impulsive-phase chromospheric properties, including: electron diagnostics, optical and UV emission, and…

Solar and Stellar Astrophysics · Physics 2012-07-03 Lyndsay Fletcher

The 2011 January 28 M1.4 flare exhibits two side-by-side candle-flame-shaped flare loop systems underneath a larger cusp-shaped structure during the decay phase, as observed at the northwestern solar limb by the Solar Dynamics Observatory…

Solar and Stellar Astrophysics · Physics 2016-04-20 Tingyu Gou , Rui Liu , Yuming Wang , Kai Liu , Bin Zhuang , Jun Chen , Quanhao Zhang , Jiajia Liu

This short paper reviews several recent key observations of the processes occurring in the lower atmosphere (chromosphere and photosphere) during flares. These are: evidence for compact and fragmentary structure in the flare chromosphere,…

Solar and Stellar Astrophysics · Physics 2013-12-02 Lyndsay Fletcher , Paulo J. A. Simoes

We present the first observations of chromospheric swirls using the Hydrogen-alpha Rapid Dynamics camera and Rapid Oscillations in the Solar Atmosphere imaging instruments at the Dunn Solar Telescope. These vortices contribute to heating…

Solar and Stellar Astrophysics · Physics 2025-09-18 Oana Vesa , Juie Shetye , Erwin Verwichte

UV bursts are transients in the solar atmosphere with an increased impulsive emission in the extreme UV lasting for one to several tens of minutes. They often show spectral profiles indicative of a bi-directional outflow in response to…

Solar and Stellar Astrophysics · Physics 2019-07-31 H. Peter , Y. -M. Huang , L. P. Chitta , P. R. Young

Extreme-ultraviolet images from the Solar Dynamics Observatory often show looplike fine structure to be present where no minority-polarity flux is visible in magnetograms, suggesting that the rate of ephemeral region (ER) emergence inside…

Solar and Stellar Astrophysics · Physics 2021-04-14 Y. -M. Wang

Coronal waves, significant solar phenomena, act as diagnostic tools for scientists studying solar atmosphere properties. Here, we present a novel observation detailing how a coronal wave event, associated with an X5.0 class flare,…

Numerical models of solar flares typically focus on the behaviour of directly-heated flare models, adopting magnetic field- aligned, plane-parallel methodologies. With high spatial- and spectral-resolution ground-based optical observations…

Solar and Stellar Astrophysics · Physics 2022-09-21 Christopher M. J. Osborne , Lyndsay Fletcher