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Related papers: Soft X-ray Pulsations in Solar Flares

200 papers

We examine SDO/EVE data to better understand solar flare irradiance, and how that irradiance may vary for large events. We measure scaling laws relating GOES flare classes to irradiance in 21 lines measured with SDO/EVE, formed across a…

Solar and Stellar Astrophysics · Physics 2022-03-14 Jeffrey W. Reep , David E. Siskind , Harry P. Warren

We present a comprehensive timing analysis on the Be/X-ray binary pulsar RX J0440.9+4431 using observations from \textit{NICER} and \textit{Insight}-HXMT during the 2022--2023 outburst. The power density spectrum (PDS) of RX J0440.9+4431…

High Energy Astrophysical Phenomena · Physics 2024-02-23 P. P. Li , L. Tao , R. C. Ma , M. Y. Ge , Q. C. Zhao , S. J. Zhao , L. Zhang , Q. C. Bu , L. D. Kong , Y. L. Tuo , L. Ji , S. Zhang , J. L. Qu , S. N. Zhang , Y. Huang , X. Ma , W. T. Ye , Q. C. Shui

Context. QPPs are usually detected as spatial displacements of coronal loops in imaging observations or as periodic shifts of line properties in spectroscopic observations. They are often applied for remote diagnostics of magnetic fields…

Solar and Stellar Astrophysics · Physics 2018-09-26 D. Li , D. Yuan , Y. N. Su , Q. M. Zhang , W. Su , Z. J. Ning

It is well known among the scientific community that solar flare activity often begins well before the main impulsive energy release. Our aim is to investigate the earliest phase of four distinct flares observed by Solar Orbiter/STIX and…

Here we present the results of the study of the north-south (N-S) distribution and asymmetry of GOES soft X-ray (SXR) flares during solar cycle 24. The period of study includes ascending, maximum and descending phases of the cycle. During…

Solar and Stellar Astrophysics · Physics 2020-07-15 Anita Joshi , Ramesh Chandra

We present systematic analysis of spatio-temporal evolution of sources of hard X-ray (HXR) pulsations in solar flares. We concentrate on disk flares whose impulsive phase are accompanied by a series of more than three peaks (pulsations) of…

Solar and Stellar Astrophysics · Physics 2016-08-25 S. A. Kuznetsov , I. V. Zimovets , A. S. Morgachev , A. B. Struminsky

We use Renewal Theory for the estimation and interpretation of the flare rate from the Geostationary Operational Environmental Satellite (GOES) soft X-ray flare catalogue. It is found, that in addition to the flare rate variability with the…

Solar and Stellar Astrophysics · Physics 2015-03-20 Andrei Gorobets , Mauro Messerotti

We embark on a study of quasi-periodic pulsations (QPPs) in the decay phase of white-light stellar flares observed by Kepler. Out of the 1439 flares on 216 different stars detected in the short-cadence data using an automated search, 56…

Solar and Stellar Astrophysics · Physics 2016-04-27 C. E. Pugh , D. J. Armstrong , V. M. Nakariakov , A. -M. Broomhall

QFP wave trains in the corona have been studied intensively in the past decade, thanks to the full-disk, high spatiotemporal resolution, and wide-temperature coverage observations taken by the SDO/AIA. In AIA observations, QFP wave trains…

Solar and Stellar Astrophysics · Physics 2022-02-23 Yuandeng Shen , Xinping Zhou , Yadan Duan , Zehao Tang , Chengrui Zhou , Song Tan

We present the result of comparison between magnetic field parameters and the intensity of X-ray emission for solar microflares with Geosynchronous Operational Environmental Satellites (GOES) classes from A0.02 to B5.1. For our study, we…

Solar and Stellar Astrophysics · Physics 2017-08-30 A. S. Kirichenko , S. A. Bogachev

Solar flares and X-ray plasma ejections (XPEs) occur simultaneously but usually are separated spatially. We present two exceptional events observed by {\sl Yohkoh} in 2001 October 2 (event 1) and 2000 October 16 (event 2), in which features…

Solar and Stellar Astrophysics · Physics 2013-03-11 Michal Tomczak

Short timescale flux variations are closely related to the energy release process of magnetic reconnection during solar flares. Radio light curves at 1, 2, 3.75, 9.4, and 17 GHz of 209 flares observed by the Nobeyama Radio Polarimeter from…

Solar and Stellar Astrophysics · Physics 2020-06-04 Wang Lu , Liu Si-ming , Ning Zong-jun

Decades of astrophysical observations have convincingly shown that soft X-ray (SXR; ~0.1--10 keV) emission provides unique diagnostics for the high temperature plasmas observed in solar flares and active regions. SXR observations critical…

Instrumentation and Methods for Astrophysics · Physics 2017-01-04 Amir Caspi , Albert Y. Shih , Harry P. Warren , Marek Stęślicki , Janusz Sylwester

The study of the localized plasma conditions before the impulsive phase of a solar flare can help us understand the physical processes that occur leading up to the main flare energy release. Here, we present evidence of a hot X-ray onset…

Solar and Stellar Astrophysics · Physics 2020-12-02 Hugh S. Hudson , Paulo J. A. Simoes , Lyndsay Fletcher , Laura A. Hayes , Iain G. Hannah

Solar flares stronger than X10 (S-flares, >X10) are the highest class flares which significantly impact on the Sun's evolution and space weather. Based on observations of Geostationary Orbiting Environmental Satellites (GOES) at soft X-ray…

Solar and Stellar Astrophysics · Physics 2025-01-10 Baolin Tan , Yin Zhang , Jing Huang , Kaifan Ji

Some 15% of solar flares having a soft X-ray flux above GOES class C5 are reported to lack coherent radio emission in the 100 - 4000 MHz range (type I - V and decimetric emissions). A detailed study of 29 such events reveals that 22 (76%)…

Astrophysics · Physics 2009-11-13 Arnold O. Benz , Roman Brajsa , Jasmina Magdalenic

Understanding how energy is released in flares is one of the central problems of solar and stellar astrophysics. Observations of high temperature flare plasma hold many potential clues as to the nature of this energy release. It is clear,…

Solar and Stellar Astrophysics · Physics 2020-05-27 Jeffrey W. Reep , Harry P. Warren , Christopher S. Moore , Crisel Suarez , Laura A. Hayes

The solar corona is full of dynamic phenomena, e.g., solar flares, micro flares in active regions, jets in coronal holes and in the polar regions, X-ray bright points in quiet regions, etc. They are accompanied by interesting physical…

Solar and Stellar Astrophysics · Physics 2017-06-15 Noriyuki Narukage , Shin-nosuke Ishikawa , Tomoko Kawate , Shinsuke Imada , Taro Sakao

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

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