English
Related papers

Related papers: Small electron acceleration episodes in the solar …

200 papers

The second Hi-C flight (Hi-C2.1) provided unprecedentedly-high spatial and temporal resolution ($\sim$250km, 4.4s) coronal EUV images of Fe IX/X emission at 172 \AA, of AR 12712 on 29-May-2018, during 18:56:21-19:01:56 UT. Three…

This paper reports on the re-analysis of solar flares in which the hard X-rays (HXRs) come predominantly from the corona rather than from the more usual chromospheric footpoints. All of the 26 previously analyzed event time intervals, over…

Solar and Stellar Astrophysics · Physics 2018-11-07 Brian R. Dennis , Miguel A. Duval-Poo , Michele Piana , Andrew R. Inglis , A. Gordon Emslie , Jingnan Guo , Yan Xu

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

The content of hot material in the corona is not constant. Soft X-ray and high-temperature EUV line observations show that new material, apparently heated and evaporated from the chromosphere, is frequently injected into the corona both in…

Astrophysics · Physics 2016-08-30 Arnold O. Benz , Paolo C. Grigis

On 17 January 2005 two fast coronal mass ejections were recorded in close succession during two distinct episodes of a 3B/X3.8 flare. Both were accompanied by metre-to-kilometre type-III groups tracing energetic electrons that escape into…

Solar and Stellar Astrophysics · Physics 2015-03-18 A. Hillaris , O. Malandraki , K. -L Klein , P. Preka-Papadema , X. Moussas , C. Bouratzis , E. Mitsakou , P. Tsitsipis , A. Kontogeorgos

Non-thermal electrons accelerated in the solar corona can produce intense coherent radio emission, known as solar type III radio bursts. This intense radio emission is often observed from hundreds of MHz in the corona down to the tens of…

Solar and Stellar Astrophysics · Physics 2014-12-10 H. Ratcliffe , E. P. Kontar , H. A. S. Reid

Solar flares are accompanied by an enhanced emission of electromagnetic waves from the radio up to the gamma-ray range. The associated hard X-ray (HXR) and microwave radiation is generated by energetic electrons, which carry a substantial…

Solar and Stellar Astrophysics · Physics 2024-04-19 G. Mann , A. M. Veronig , F. Schuller

The physical processes causing energy exchange between the Sun's hot corona and its cool lower atmosphere remain poorly understood. The chromosphere and transition region (TR) form an interface region between the surface and the corona that…

We report on four large filament eruptions (FEs) from solar cycles 23 and 24 that were associated with large solar energetic particle (SEP) events and interplanetary type II radio bursts. The post-eruption arcades corresponded to mostly…

Solar and Stellar Astrophysics · Physics 2015-06-11 N. Gopalswamy , P. Makela , S. Akiyama , S. Yashiro , H. Xie , N. Thakur , S. W. Kahler

[Abridged]We present analysis of a pair of unusually energetic coronal hard X-ray (HXR) sources detected by RHESSI during the impulsive phase of an X3.9 class solar flare on 2003 November 3, which simultaneously shows two intense footpoint…

Solar and Stellar Astrophysics · Physics 2015-06-03 Qingrong Chen , Vahe Petrosian

Small-scale eruptions could play an important role in coronal heating, generation of solar energetic particles (SEPs), and mass source of the solar wind. However, they are poorly observed, and their characteristics, distributions, and…

Solar and Stellar Astrophysics · Physics 2024-10-24 Rui Wang , Ying D. Liu , Xiaowei Zhao , Huidong Hu

The excess temperature of the solar corona over the photosphere poses a challenge. Multiple energetic events contribute to maintaining the corona at such high temperatures. The energy released in different events can vary across several…

Solar and Stellar Astrophysics · Physics 2023-02-21 Abhishek Rajhans

We carried out detailed analysis of X-ray and radio observations of a simple flare loop that occurred on 12th August 2002, with the impulsive hard X-ray (HXR) light curves dominated by a single pulse. The emission spectra of the early…

Solar and Stellar Astrophysics · Physics 2015-06-22 I. N. Sharykin , S. Liu , L. Fletcher

Particle acceleration is one of the most significant features that are ubiquitous among space and cosmic plasmas. It is most prominent during flares in the case of the Sun, with which huge amount of electromagnetic radiation and high-energy…

Solar and Stellar Astrophysics · Physics 2014-05-15 Noriyuki Narukage , Masumi Shimojo , Taro Sakao

Observations with {\em RHESSI} have enabled the detailed study of the structure of dense hard X-ray coronal sources in solar flares. The variation of source extent with electron energy has been discussed in the context of streaming of…

Solar and Stellar Astrophysics · Physics 2015-06-19 Natasha L. S. Jeffrey , Eduard P. Kontar , Nicolas H. Bian , A. Gordon Emslie

The existence of the million-degree corona above the cooler photosphere is an unsolved problem in astrophysics. Detailed study of quiescent corona that exists regardless of the phase of the solar cycle may provide fruitful hints towards…

Solar and Stellar Astrophysics · Physics 2022-12-07 Vishal Upendran , Durgesh Tripathi , N. P. S. Mithun , Santosh Vadawale , Anil Bhardwaj

We investigate the type III radio bursts and X-ray signatures of accelerated electrons in a well observed solar flare in order to find the spatial properties of the acceleration region. Combining simultaneous RHESSI hard X-ray flare data…

Solar and Stellar Astrophysics · Physics 2015-05-27 H. A. S. Reid , N. Vilmer , E. P. Kontar

We compare the characteristics of flare-accelerated energetic electrons at the Sun with those injected into interplanetary space. We have identified 17 energetic electron events well-observed with the SEPT instrument aboard STEREO which…

Solar and Stellar Astrophysics · Physics 2021-10-20 Nina Dresing , A. Warmuth , F. Effenberger , K. -L. Klein , S. Musset , L. Glesener , M. Brüdern

A number of double coronal X-ray sources have been observed during solar flares by RHESSI, where the two sources reside at different sides of the inferred reconnection site. However, where and how are these X-ray-emitting electrons…

Solar and Stellar Astrophysics · Physics 2022-07-20 Xiangliang Kong , Jing Ye , Bin Chen , Fan Guo , Chengcai Shen , Xiaocan Li , Sijie Yu , Yao Chen , Joe Giacalone