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Related papers: Flare Induced Photospheric Velocity Diagnostics

200 papers

We have carried out the first comprehensive investigation of enhanced line emission from molecular hydrogen, H$_{2}$ at 1333.79 {\AA}, observed at flare ribbons in SOL2014-04-18T13:03. The cool H$_{2}$ emission is known to be fluorescently…

Solar and Stellar Astrophysics · Physics 2021-02-24 Sargam M. Mulay , Lyndsay Fletcher

This paper presents a detailed study of excess line broadening in EUV emission lines during the impulsive phase of a C-class solar flare. In this work, which utilizes data from the EUV Imaging Spectrometer (EIS) onboard Hinode, the…

Solar and Stellar Astrophysics · Physics 2012-02-09 Ryan O. Milligan

The IRIS Mg II k line serves as a very good tool to diagnose the heating processes in solar flares. Recent studies have shown that apart from the usual red asymmetries which are interpreted as the result of condensation downflows, this line…

Solar and Stellar Astrophysics · Physics 2020-04-23 Jie Hong , Ying Li , M. D. Ding , Yu-Hao Zhou

RHESSI and Hinode observations of a GOES B-class flare are combined to investigate the origin of 15 MK plasma. The absence of any detectable hard X-ray emission coupled with weak blueshifted emission lines (indicating upward velocities…

Solar and Stellar Astrophysics · Physics 2010-03-03 Ryan O. Milligan

We study the chromospheric LOS velocities during the GOES M3.2 flare (SOL2013-05-17T08:43) using simultaneous spectroscopic data of the He I 1083.0 nm triplet and Ca II 854.2 nm line. A filament was present in the flaring area. The…

Solar and Stellar Astrophysics · Physics 2025-07-09 C. Kuckein , M. Collados , A. Asensio Ramos , C. J. Díaz Baso , T. Felipe , C. Quintero Noda , L. Kleint , L. Fletcher , S. Matthews

The strong correlation between energy injection and mid-infrared (mid-IR) emission observed during solar flares can be used to probe energy deposition throughout the chromosphere, since the IR tracks prompt flare-induced changes in electron…

Solar and Stellar Astrophysics · Physics 2026-05-08 Miguel Rojas-Quesada , Lyndsay Fletcher , Hugh Hudson , Sargam M. Mulay , Paulo J. A. Simoes

We explore the response of the He II 304 {\AA} and He I 584 {\AA} line intensities to electron beam heating in solar flares using radiative hydrodynamic simulations. Comparing different electron beams parameters, we found that the…

Solar and Stellar Astrophysics · Physics 2015-12-14 Paulo J. A. Simões , Lyndsay Fletcher , Nicolas Labrosse , Graham S. Kerr

Extreme precision radial-velocity spectrometers enable extreme precision stellar spectroscopy. Searches for low-mass exoplanets around solar-type stars are limited by the physical variability in stellar spectra, such as the short-term…

Solar and Stellar Astrophysics · Physics 2023-11-01 Dainis Dravins , Hans-Günter Ludwig

Magnetic reconnection is believed to be the dominant energy release mechanism in solar flares. The standard flare model predicts both downward and upward outflow plasmas with speeds close to the coronal Alfv\'{e}n speed. Yet, spectroscopic…

Solar and Stellar Astrophysics · Physics 2014-12-02 Hui Tian , Gang Li , Katharine K. Reeves , John C. Raymond , Fan Guo , Wei Liu , Bin Chen , Nicholas A. Murphy

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

The 2014 March 29 X1 solar flare (SOL20140329T17:48) produced bright continuum emission in the far- and near-ultraviolet (NUV) and highly asymmetric chromospheric emission lines, providing long-sought constraints on the heating mechanisms…

Solar and Stellar Astrophysics · Physics 2017-02-17 Adam F. Kowalski , Joel C. Allred , Adrian N. Daw , Gianna Cauzzi , Mats Carlsson

The X-class solar flare of October 23, 2012, generated continuum photospheric emission and a strong helioseismic wave ("sunquake") that points to an intensive energy release in the dense part of the solar atmosphere. We study properties of…

Solar and Stellar Astrophysics · Physics 2017-07-19 Ivan N Sharykin , Alexander G Kosovichev , Viacheslav M Sadykov , Ivan V Zimovets , Ivan I Myshyakov

The Hydrogen Balmer series is a basic radiative loss channel from the flaring solar chromosphere. We report here on the analysis of an extremely rare set of simultaneous observations of a solar flare in the H${\alpha}$ and H${\beta}$ lines…

For many years various asymmetrical profiles of different spectral lines emitted from solar flares have been frequently observed. These asymmetries or line shifts are caused predominantly by vertical mass motions in flaring layers and they…

Astrophysics · Physics 2007-05-23 A. Berlicki

With observations of IRIS, we study chromospheric heating and evaporation during an M1.6 flare SOL2015-03-12T11:50. At the flare ribbons, the Mg II 2791.59 line shows quasi-periodic short-duration red-wing enhancement, which is likely…

Solar and Stellar Astrophysics · Physics 2018-04-04 H. Tian , N. -H. Chen

Flarix is a radiation-hydrodynamical (RHD) code for modeling of the response of the chromosphere to a beam bombardment during solar flares. It solves the set of hydrodynamic conservation equations coupled with non-LTE equations of radiative…

Solar and Stellar Astrophysics · Physics 2017-01-11 P. Heinzel , J. Kasparova , M. Varady , M. Karlicky , Z. Moravec

Context. Radiative losses are an indispensable part in the numerical simulation of flares. Detailed calculations could be computationally expensive, especially in the chromosphere. There have been some approximate recipes for chromospheric…

Solar and Stellar Astrophysics · Physics 2022-12-14 J. Tian , J. Hong , Y. Li , M. D. Ding

Much of a solar flare's energy is thought to be released in the continuum. The optical continuum (white light) is of special interest due to the ability to observe it from the ground. We aim to investigate the prevalence of white-light (WL)…

Solar and Stellar Astrophysics · Physics 2026-01-21 Sascha Ornig , Mats Carlsson

We have calculated the H$\alpha$ and Ca {\sc ii} 8542 {\AA} line profiles based on four different atmospheric models, including the effects of nonthermal electron beams with various energy fluxes. These two lines have different responses to…

Astrophysics · Physics 2008-11-26 J. X. Cheng , M. D. Ding , J. P. Li

We investigate observational signatures of explosive chromospheric evaporation during a white-light flare (WLF) that occurred on 2022 August 27. Using the moment analysis, bisector techniques, and the Gaussian fitting method, red-shifted…

Solar and Stellar Astrophysics · Physics 2023-06-29 Dong Li , Chuan Li , Ye Qiu , Shihao Rao , Alexander Warmuth , Frederic Schuller , Haisheng Zhao , Fanpeng Shi , Jun Xu , Zongjun Ning