English
Related papers

Related papers: Solar Flare X-ray Source Motion as a Response to E…

200 papers

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

We compare time variations of the H$\alpha$ and X-ray emissions observed during the pre-impulsive and impulsive phases of the C1.1-class solar flare on 21 June 2013 with those of plasma parameters and synthesized X-ray emission from a…

Solar and Stellar Astrophysics · Physics 2017-10-04 R. Falewicz , K. Radziszewski , P. Rudawy , A. Berlicki

Most theoretical descriptions of the production of solar flare bremsstrahlung radiation assume the collision of dilute accelerated particles with a cold, dense target plasma, neglecting interactions of the fast particles with each other.…

Solar and Stellar Astrophysics · Physics 2015-05-18 R. K. Galloway , P. Helander , A. L. MacKinnon , J. C. Brown

The newly developed X-ray visibility forward fitting technique is applied to Reuven Ramaty High Energy Solar Spectroscopic Imager (RHESSI) data of a limb flare to investigate the energy and height dependence on sizes, shapes, and position…

Solar and Stellar Astrophysics · Physics 2015-05-18 E. P. Kontar , I. G. Hannah , N. L. S. Jeffrey , M. Battaglia

The well-established notion of a "common population" of the accelerated electrons simultaneously producing the hard X-ray (HXR) and the microwave (MW) emission during the flare impulsive phase has been challenged by some studies reporting…

Solar and Stellar Astrophysics · Physics 2018-01-10 Natsuha Kuroda , Dale E. Gary , Haimin Wang , Gregory Fleishman , Gelu M. Nita , Ju Jing

X-ray observations are a direct diagnostic of fast electrons produced in solar flares, energized during the energy release process and directed towards the Sun. Since the properties of accelerated electrons can be substantially changed…

Solar and Stellar Astrophysics · Physics 2015-10-28 Natasha Jeffrey , Eduard Kontar , Gordon Emslie , Nicolas Bian

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

The solar corona is orders of magnitude hotter than the underlying photosphere, but how the corona attains such high temperatures is still not understood. Soft X-ray (SXR) emission provides important diagnostics for thermal processes in the…

Solar and Stellar Astrophysics · Physics 2015-09-15 Amir Caspi , Thomas N. Woods , Harry P. Warren

We report on the Fermi-LAT detection of high-energy emission from the behind-the-limb (BTL) solar flares that occurred on 2013 October 11, and 2014 January 6 and September 1. The Fermi-LAT observations are associated with flares from active…

Recent measurements of vertical extents and positions of the chromospheric hard X-ray (HXR) flare sources based on Ramaty High-Energy Spectroscopic Imager (RHESSI) observations show a significant inconsistency with the theoretical…

Solar and Stellar Astrophysics · Physics 2016-12-07 Z. Moravec , M. Varady , J. Kasparova , D. Kramolis

We report observations of white-light ejecta in the low corona, for two X-class flares on the 2013 May 13, using data from the Helioseismic and Magnetic Imager (HMI) of the Solar Dynamics Observatory. At least two distinct kinds of sources…

X-ray emission provides the most direct diagnostics of the energy-release process in solar flares. Occasionally, a superhot X-ray source is found to be above hot flare loops of ~10 MK temperature. While the origin of the superhot plasma is…

Solar and Stellar Astrophysics · Physics 2022-02-09 Zhenjun Zhou , Rui Liu , Jianqing Sun , Jie Zhang , Mingde Ding , Yuming Wang , Xiaoyu Yu , Lijuan Liu , Jun Cui

X-ray and EUV observations are an important diagnostic of various plasma parameters of the solar atmosphere during solar flares. Soft X-ray and EUV observations often show coronal sources near the top of flaring loops, while hard X-ray…

Solar and Stellar Astrophysics · Physics 2015-06-11 Marina Battaglia , Eduard P. Kontar

We present new constraints on the high-temperature emission measure of a non-flaring solar active region using observations from the recently flown Focusing Optics X-ray Solar Imager sounding rocket payload. FOXSI has performed the first…

A M-class behind-the-limb solar flare on 1 May 2013 (SOL2013-05-01T02:32), accompanied by a ($\sim$ 400 km/s) CME was observed by several space-based observatories with different viewing angles. We investigated the RHESSI-observed occulted…

The bulk of solar flare emission originates from very compact sources located in the lower solar atmosphere and seen in various wavelength ranges: near optical, UV, EUV, soft and hard X-rays, and gamma-ray emission, yet very few spatially…

Solar and Stellar Astrophysics · Physics 2015-05-28 Marina Battaglia , Eduard P. Kontar

The optical and near-ultraviolet (NUV) continuum radiation in M dwarf flares is thought to be the impulsive response of the lower stellar atmosphere to magnetic energy release and electron acceleration at coronal altitudes. This radiation…

Solar and Stellar Astrophysics · Physics 2023-02-07 Adam F. Kowalski

It is generally accepted that densities of quiet sun and active region plasma are sufficiently low to justify the optically thin approximation, and it is commonly used in the analysis of line emissions from plasma in the solar corona.…

Solar and Stellar Astrophysics · Physics 2018-02-14 Edward Thiemann , Phillip Chamberlin , Francis Eparvier , Luke Epp

The aim of the present paper is to use quasi-periodic oscillations in hard X-rays (HXRs) of solar flares as a diagnostic tool for investigation of impulsive electron acceleration. We have selected a number of flares which showed…

Solar and Stellar Astrophysics · Physics 2015-05-13 J. Jakimiec , M. Tomczak

The aim of this study is to generate maps of the hard X-ray emission produced by energetic electrons in a solar flare and compare them with observations. The ultimate goal is to test the viability of the combined MHD/test-particle approach…

Solar and Stellar Astrophysics · Physics 2020-11-04 Mykola Gordovskyy , Philippa K. Browning , Satoshi Inoue , Eduard P. Kontar , Kanya Kusano , Grigory E. Vekstein