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Related papers: Soft X-ray Pulsations in Solar Flares

200 papers

The Sun offers a convenient nearby laboratory to study the physical processes of particle acceleration and impulsive energy release in magnetized plasmas that occur throughout the universe, from planetary magnetospheres to black hole…

Solar and Stellar Astrophysics · Physics 2011-05-13 Amir Caspi

We investigate the August 9, 2011 solar flare of X-ray class X6.9, the "hottest" flare from 2000 to 2012, with a peak plasma temperature according to GOES data of 32.5 MK. Our goal is to determine the cause of such an anomalously high…

Solar and Stellar Astrophysics · Physics 2015-06-23 I. N. Sharykin , A. B. Struminsky , I. V. Zimovets

We have performed a timing and spectral analysis of the X-ray pulsar SWIFT J1626.6-5156 during a major X-ray outburst in order to unveil its nature and investigate its flaring activity. Epoch- and pulse-folding techniques were used to…

Astrophysics · Physics 2009-11-13 P. Reig , T. Belloni , G. L. Israel , S. Campana , N. Gehrels , J. Homan

Solar flares are the most powerful explosions occurring in the solar system, which may lead to disastrous space weather events and impact various aspects of our Earth. So far, it is still a big challenge in modern astrophysics to understand…

Solar and Stellar Astrophysics · Physics 2016-12-28 Baolin Tan , Zhiqiang Yu , Jing Huang , Chengming Tan , Yin Zhang

Solar flares are explosive releases of magnetic energy stored in the solar corona, driven by magnetic reconnection. These events accelerate electrons, generating hard X-ray emissions and often display Quasi Periodic Pulsations (QPPs) across…

Solar and Stellar Astrophysics · Physics 2025-11-25 Luiz A. C. A. Schiavo , Natasha L. S. Jeffrey , Gert J. J. Botha , James A. McLaughlin

We report the discovery of phase shifts between X-ray pulses at different energies in the newly discovered millisecond (ms) X-ray pulsar SAX J1808.4-3658. The results show that low-energy pulses lag high-energy pulses by as much as…

Astrophysics · Physics 2009-10-30 Wei Cui , Edward H. Morgan , Lev G. Titarchuk

We analyse the 30 October, 2004, X1.2/SF solar event that occurred in AR 10691 (N13 W18) at around 11:44 UT. Observations at 212 and 405 GHz of the Solar Submillimeter Telescope (SST), with high time resolution (5 ms), show an intense…

We present the analyses of intense X-ray flares detected on the active fast rotator AB Dor using observations from the XMM-Newton. A total of 21 flares are detected, and 13 flares are analysed in detail. The total X-ray energy of these…

Solar and Stellar Astrophysics · Physics 2023-10-23 Shweta Didel , Jeewan C. Pandey , A. K. Srivastava , Gurpreet Singh

We analyzed the soft X-ray light curves from the {\sl Geostationary Operational Environmental Satellites (GOES)} over the last 37 years (1975-2011) and measured with an automated flare detection algorithm over 300,000 solar flare events…

Solar and Stellar Astrophysics · Physics 2012-07-18 Markus J. Aschwanden , Samuel L. Freeland

Using Gaussian process methods, we analyzed the light curves of three extreme solar X-ray flares observed by the RHESSI satellite. Their variability characteristics were then compared with those of HXMT-HE X-ray burst (XRB; in SGR…

High Energy Astrophysical Phenomena · Physics 2025-12-15 Haiyun Zhang , Dahai Yan , Lijuan Dong , Ping Zhang , Ruijing Tang , Jianeng Zhou , Lian Tao , Li Zhang , Niansheng Tang

Non-thermal and thermal parameters of 85 solar flares of GOES class B1 to M6 (background subtracted classes A1 to M6) have been compared to each other. The hard X-ray flux has been measured by RHESSI and a spectral fitting provided flux and…

Astrophysics · Physics 2009-11-11 Marina Battaglia , Paolo C. Grigis , Arnold O. Benz

We analyze 19 bright variable X-ray sources detected in the XMM-Newton Extended Survey of the Taurus Molecular Cloud (XEST), in order to characterize the variations with time of their coronal properties and to derive informations on the…

About the driven mechanisms of the quasi-periodic fast-propagating (QFP) wave trains, there exist two dominant competing physical explanations: associated with the flaring energy release or attributed to the waveguide dispersion. Employing…

Solar and Stellar Astrophysics · Physics 2022-12-21 Xinping Zhou , Yuandeng Shen , Hongfei Liang , Zhining Qu , Yadan Duan , Zehao Tang , Chengrui Zhou , Song Tan

In this study we determine scaling relationships of observed solar flares that can be used to predict upper limits of the GOES-class magnitude of solar flares. The flare prediction scheme is based on the scaling of the slowly-varying…

Solar and Stellar Astrophysics · Physics 2020-07-15 Markus J. Aschwanden

We present the results of an analysis of hard X-ray observations of the C2.7 solar flare detected by the RT-2 Experiment onboard the Coronas - Photon satellite. We detect hard X-ray pulsations at periods of ~12 s and ~15 s. We find a…

We have explored the relationship between hard X-ray (HXR) emissions and Doppler velocities caused by the chromospheric evaporation in two X1.6 class solar flares on 2014 September 10 and October 22, respectively. Both events display double…

Solar and Stellar Astrophysics · Physics 2015-11-04 Dong Li , Zongjun Ning , Qingmin Zhang

We present multi-wavelength analysis of a quasi-periodic pulsation (QPP) observed in the hard X-ray, radio, and extreme-ultraviolet (EUV) channels during an M1.9 flare occurred on 23-24 September 2011. The non-thermal hard X-ray emission in…

Solar and Stellar Astrophysics · Physics 2016-05-04 Pankaj Kumar , Valery M. Nakariakov , Kyung-Suk Cho

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

We studied a solar flare with pronounced quasi-periodic pulsations detected in the microwave, X-ray, and radio bands. We used the methods of correlation, Fourier, and wavelet analyses to examine the temporal fine structures and…

Solar and Stellar Astrophysics · Physics 2016-08-02 E. G. Kupriyanova , L. K. Kashapova , H. A. S. Reid , I. N. Myagkova

We present a statistical study of chromospheric evaporation in solar flares using simultaneous observations by the RHESSI X-ray telescope and the IRIS UV spectrograph. The results are compared with radiation hydrodynamic flare models from…

Solar and Stellar Astrophysics · Physics 2019-01-23 Viacheslav M Sadykov , Alexander G Kosovichev , Ivan N Sharykin , Graham S Kerr