English
Related papers

Related papers: Soft X-ray Pulsations in Solar Flares

200 papers

Solar flares sometimes lead to coronal mass ejections that directly affect the Earth's environment. However, a large fraction of flares, including on solar-type stars, are confined flares. What are the differences in physical properties…

Solar and Stellar Astrophysics · Physics 2023-10-18 Maria D. Kazachenko

We report solar flare plasma to be multi-thermal in nature based on the theoretical model and study of the energy-dependent timing of thermal emission in ten M-class flares. We employ high-resolution X-ray spectra observed by the Si…

Solar and Stellar Astrophysics · Physics 2011-03-30 Rajmal Jain , Arun Kumar Awasthi , Arvind Singh Rajpurohit , Markus J. Aschwanden

A large arcade flare of 2 March 1993 has been investigated using X-ray observations recorded by the {\sl Yohkoh} and GOES satellites and the {\sl Compton Gamma Ray Observatory}. We analyzed quasi-periodicity of the hard-X-ray (HXR) pulses…

Solar and Stellar Astrophysics · Physics 2015-06-18 Jerzy Jakimiec , Michal Tomczak

We perform X-ray spectral and timing analyses of solar-like (spectral types F5--K8) and intermediate-type (B4--F4) Pleiads observed in a 40-ks XMM-Newton EPIC exposure. All 8 solar-like members have ``quasi-steady'' \lx $\ga 10^{29}$ erg/s…

Astrophysics · Physics 2009-11-10 K. R. Briggs , J. P. Pye

Solar flares (SFs) are sudden brightening observed over the Sun surface which is associated with a large energy release. Flares with burst of Xray emission are normally followed by a mass ejection of electrons and ions from the solar…

Solar and Stellar Astrophysics · Physics 2022-02-03 Kamsali Nagaraja , Praveen Kumar Basuvaraj , S. C. Chakravarty

Flares that are orders of magnitude larger than the most energetic solar flares are routinely observed on Sun-like stars, raising the question of whether the same physical processes are responsible for both solar and stellar flares. In this…

Solar and Stellar Astrophysics · Physics 2015-10-28 Chloe E. Pugh , Valery M. Nakariakov , Anne-Marie Broomhall

The accelerated electrons during solar flares produce radio bursts and nonthermal X-ray signatures. The quasi-periodic pulsations (QPPs) and fine structures in spatial-spectral-temporal space in radio bursts depend on the emission mechanism…

Solar and Stellar Astrophysics · Physics 2024-05-08 Rohit Sharma , Marina Battaglia , Sijie Yu , Bin Chen , Yingjie Luo , Sam Krucker

There is evidence that coronal heating is highly intermittent, and flares are the high energy extreme. The properties of the heat pulses are difficult to constrain. Here hydrodynamic loop modeling shows that several large amplitude…

Solar and Stellar Astrophysics · Physics 2016-08-03 F. Reale

Context. We present an analysis of a GOES M1.8 flare with excellent observational coverage in UV, EUV, and X-ray, including observations from the instruments IRIS, SDO with AIA, Hinode/EIS, Hinode/XRT, and Solar Orbiter with the…

Recent irradiance measurements from numerous heliophysics and astrophysics missions including SDO, GOES, Kepler, TESS, Chandra, XMM-Newton, and NICER have provided critical input in understanding the physics of the most powerful transient…

Solar and Stellar Astrophysics · Physics 2023-09-11 Jeffrey W. Reep , Vladimir S. Airapetian

Post-flare arcades are well-known components of solar flare evolution, which have been observed for several decades. Coronal rain, cascades of catastrophically-cooled plasma, outline the loops and provide eye-catching evidence of the recent…

Solar and Stellar Astrophysics · Physics 2022-11-09 Emily I. Mason , Kara L. Kniezewski

Solar flare emission at X-ray and extreme ultraviolet (EUV) energies can cause substantial enhancements in the electron density in the Earth's lower ionosphere. It is now become clear that flares exhibit quasi-periodic pulsations with…

Decayless kink oscillations, which are nearly omnipresent in the solar corona, are believed to be driven by continuously operating energy supply. In this letter, we investigate an external continuous excitation of an apparent decayless…

Solar and Stellar Astrophysics · Physics 2023-11-29 Dong Li , Zhentong Li , Fanpeng Shi , Yang Su , Wei Chen , Fu Yu , Chuan Li , Ye Qiu , Yu Huang , Zongjun Ning

Very long-periodic pulsations during preflare phases (preflare-VLPs) have been detected in the full-disk solar soft X-Ray (SXR) flux (see Tan et al. 2016). They may be regarded as precursors to solar flares and may help us better understand…

Solar and Stellar Astrophysics · Physics 2020-07-15 Dong Li , Song Feng , Wei Su , Yu Huang

The recent discovery of impulsive solar burst emission in the 30 THz band is raising new interpretation challenges. One event associated with a GOES M2 class flare has been observed simultaneously in microwaves, H-alpha, EUV, and soft X-ray…

We report the discovery of milli-hertz (mHz) quasi-periodic oscillations (QPOs) and QPO-modulated pulsations during large X-ray flares from the high-mass X-ray binary pulsar LMC X-4 using data from the Rossi X-Ray Timing Explorer (RXTE).…

Astrophysics · Physics 2009-11-06 Dae-Sik Moon , Stephen. S. Eikenberry

On 2011 May 30, quasi-periodic fast propagating (QFP) magnetosonic waves accompanied by a C2.8 flare were directly imaged by the Atomospheric Imaging Assembly instrument on board the Solar Dynamics Observatory. The QFP waves successively…

Solar and Stellar Astrophysics · Physics 2015-06-04 Yuandeng Shen , Yu Liu

In this paper, we report on the analysis of the peculiar X-ray variability displayed by the accreting millisecond X-ray pulsar IGR J00291+5934 in a 80 ks-long joint NuSTAR and XMM-Newton observation performed during the source outburst in…

High Energy Astrophysical Phenomena · Physics 2017-01-18 C. Ferrigno , E. Bozzo , A. Sanna , F. Pintore , A. Papitto , A. Riggio , L. Burderi , T. Di Salvo , R. Iaria , A. D'Aì

Analysis of spectra obtained with the gamma-ray spectrometer SPI onboard INTEGRAL of the GOES X17-class flare on October 28, 2003 is presented. In the energy range 600 keV - 8 MeV three prominent narrow lines at 2.223, 4.4 and 6.1 MeV,…

Astrophysics · Physics 2009-11-11 J. Kiener , M. Gros , V. Tatischeff , G. Weidenspointner

Apparent slipping motions of flare ribbon kernels and the formation of hard X-ray (HXR) footpoints are important signatures of magnetic reconnection in solar flares. Ultraviolet (UV) and HXR ribbon emission can show quasi-periodic…

Solar and Stellar Astrophysics · Physics 2026-04-21 Juraj Lorincik , Hannah Collier , Vanessa Polito , Laura A. Hayes , William H. Ashfield , Nabil Freij