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Related papers: Coronal hard X-ray sources revisited

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Context. High energy electrons accelerated during solar flare are abundant in the solar corona and in the interplanetary space. Commonly, the number and the energy of non-thermal electrons at the Sun is estimated using hard X-ray (HXR)…

Solar and Stellar Astrophysics · Physics 2015-06-03 E. P. Kontar , H. Ratcliffe , N. H. Bian

In this paper, we propose that the accelerated electrons in the quiet Sun could collide with the solar atmosphere to emit Hard X-rays (HXRs) via non-thermal bremsstrahlung, while some of these electrons would move upwards and escape into…

Solar and Stellar Astrophysics · Physics 2016-05-31 Wen Wang , Linghua Wang , Sam Krucker , Iain Hannah

We present the statistical analysis of 33 flare-related coronal jets, and discuss the link between the jet and the flare properties in these events. We selected jets that were observed between 2010 and 2016 by the Atmospheric Imaging…

Solar and Stellar Astrophysics · Physics 2020-02-12 Sophie Musset , Mariana Jeunon , Lindsay Glesener

We study the energetics of nonthermal electrons produced in small acceleration episodes in the solar corona. We carried out an extensive survey spanning 2004--2015 and shortlisted 6 impulsive electron events detected at 1 AU that was not…

Solar and Stellar Astrophysics · Physics 2017-11-20 Tomin James , Prasad Subramanian , Eduard P Kontar

Observations in the Mg XII 8.42 AA line onboard the CORONAS-F satellite have revealed compact high temperature objects-hot X-ray points (HXP)-and their major physical parameters were investigated. Time dependencies of temperature, emission…

Solar and Stellar Astrophysics · Physics 2015-09-25 Anton Reva , Sergey Shestov , Sergey Bogachev , Sergey Kuzin

Long-lasting, intense, stellar X-ray flares may approach conditions of breaking magnetic confinement and evolving in open space. We explore this hypothesis with hydrodynamic simulations of flares occurring in a non-confined corona: model…

Astrophysics · Physics 2009-11-07 F. Reale , F. Bocchino , G. Peres

We investigate quasi-periodic coronal pulsations during the decay phase of an X 3.2 class flare on 14 May 2013, using soft X-ray data from the RHESSI satellite. Periodogram analyses of soft X-ray light curves show that 53 s and 72 s periods…

Solar and Stellar Astrophysics · Physics 2016-01-20 Partha Chowdhury , A. K. Srivastava , B. N. Dwivedi , Robert Sych , Y. -J. Moon

For the first time, we have used RHESSI's spatial and energy resolution to determine the combined chromospheric and coronal density profile of the flaring solar atmosphere in a statistical manner, using a dataset of 838 flares observable in…

Solar and Stellar Astrophysics · Physics 2015-06-03 Pascal Saint-Hilaire , Sam Krucker , Robert P. Lin

We examine effects on the charge states of energetic ions associated with gradual solar flares due to shock heating and stripping at high ion velocities. Recent measurements of the mean charges of various elements after the flares of 1992…

Astrophysics · Physics 2009-10-30 D. Ruffolo

Based on a sample of 1114 flares observed simultaneously in hard X-rays (HXR) by the BATSE instrument and in soft X-rays (SXR) by GOES, we studied several aspects of the Neupert effect and its interpretation in the frame of the…

Astrophysics · Physics 2009-11-07 A. Veronig , B. Vrsnak , B. R. Dennis , M. Temmer , A. Hanslmeier , J. Magdalenic

The feature of quasi-periodic pulsations (QPPs) is frequently observed in the light curve of solar and stellar flares. In this letter, we investigated the QPP at a shorter period in high-energy channels of HXRs and Ggamma-ray continuum…

Solar and Stellar Astrophysics · Physics 2025-02-21 Dong Li

The standard flare model, despite its success, is limited in comprehensively explaining the various processes involving nonthermal particles. One such missing ingredient is a detailed understanding of the various processes involved during…

Solar and Stellar Astrophysics · Physics 2024-04-23 Surajit Mondal , Andrea F. Battaglia , Bin Chen , Sijie Yu

We present detailed 3D modeling of a dense, coronal thick target X-ray flare using the GX Simulator tool, photospheric magnetic measurements, and microwave imaging and spectroscopy data. The developed model offers a remarkable agreement…

Solar and Stellar Astrophysics · Physics 2016-01-13 Gregory D. Fleishman , Yan Xu , Gelu N. Nita , Dale E. Gary

We study the correlation between abrupt permanent changes of magnetic field during X-class flares observed by the GONG and HMI instruments, and the hard X-ray (HXR) emission observed by RHESSI, to relate the photospheric field changes to…

Solar and Stellar Astrophysics · Physics 2015-05-05 O. Burtseva , J. C. Martínez-Oliveros , G. J. D. Petrie , A. A. Pevtsov

In the standard model, magnetic reconnection at a vertical current sheet above the flare arcade is key to explaining many aspects of solar eruptions. The supra-arcade region is where the vertical current sheet is supposedly located, and…

Solar and Stellar Astrophysics · Physics 2025-12-23 Hanya Pan , Astrid M. Veronig , Rui Liu

Sudden jets of collimated plasma arise from many locations on the Sun, including active regions. The magnetic field along which a jet emerges is often open to interplanetary space, offering a clear "escape route" for any flare-accelerated…

Solar and Stellar Astrophysics · Physics 2018-11-07 Lindsay Glesener , Gregory D. Fleishman

We study the non-thermal emissions in a solar flare occurring on 2003 May 29 by using RHESSI hard X-ray (HXR) and Nobeyama microwave observations. This flare shows several typical behaviors of the HXR and microwave emissions: time delay of…

Astrophysics · Physics 2009-11-13 T. Minoshima , T. Yokoyama , N. Mitani

Solar flares result from the rapid conversion of stored magnetic energy within the Sun's corona. These energy releases are associated with coronal magnetic loops, which are rooted in dense photospheric plasma and are passively transported…

Solar and Stellar Astrophysics · Physics 2025-03-28 M. Berretti , S. Mestici , L. Giovannelli , D. Del Moro , M. Stangalini , F. Giannattasio , F. Berrilli

Context. Hard X-ray (HXR) spikes refer to fine time structures on timescales of seconds to milliseconds in high-energy HXR emission profiles during solar flare eruptions. Aims. We present a preliminary statistical investigation of temporal…

Solar and Stellar Astrophysics · Physics 2015-06-11 J. X. Cheng , J. Qiu , M. D. Ding , H. Wang

We investigate the solar flare of 20 October 2002. The flare was accompanied by quasi-periodic pulsations (QPP) of both thermal and nonthermal hard X-ray emissions (HXR) observed by RHESSI in the 3-50 keV energy range. Analysis of the HXR…

Solar and Stellar Astrophysics · Physics 2015-05-14 I. V. Zimovets , A. B. Struminsky
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