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Related papers: Soft X-ray microflares

200 papers

Observations in the Mg XII 8.42 AA line onboard the CORONAS-F satellite have revealed compact high temperature objects-hot X-ray points (HXP)-and their major physical parameters were investigated. Time dependencies of temperature, emission…

Solar and Stellar Astrophysics · Physics 2015-09-25 Anton Reva , Sergey Shestov , Sergey Bogachev , Sergey Kuzin

The routinely flaring events from \sgras\ trace dynamic, high-energy processes in the immediate vicinity of the supermassive black hole. We statistically study temporal and spectral properties, as well as fluence and duration distributions,…

High Energy Astrophysical Phenomena · Physics 2017-10-20 Qiang Yuan , Q. Daniel Wang , Siming Liu , Kinwah Wu

The heating of the solar corona is one of the big questions in astrophysics. Rapid pulses called nanoflares are among the best candidate mechanisms. The analysis of the time variability of coronal X-ray emission is potentially a very useful…

Solar and Stellar Astrophysics · Physics 2012-01-27 S. Terzo , F. Reale , M. Miceli , R. Kano , S. Tsuneta , J. A. Klimchuk

Hard x-ray spectral breaks are explained in terms of a 1D model with a co-spatial return current. We study 19 flares observed by RHESSI (Ramaty High Energy Solar Spectroscopic Imager) with strong spectral breaks at energies around a few…

Solar and Stellar Astrophysics · Physics 2018-01-08 Meriem Alaoui , Gordon Holman

We have statistically analyzed a set of 115 low frequency (Deca- Hectometer wavelengths range) type II and type III bursts associated with major Solar Energetic Particle (SEP: Ep > 10 MeV) events and their solar causes such as solar flares…

Solar and Stellar Astrophysics · Physics 2020-07-14 P. Pappa Kalaivani , A. Shanmugaraju , O. Prakash , R. -S. Kim

We present an updated catalog of 113 X-ray flares detected by Swift in the ~33% of the X-ray afterglows of Gamma-Ray Bursts (GRB). 43 flares have a measured redshift. For the first time the analysis is performed in 4 different X-ray energy…

High Energy Astrophysical Phenomena · Physics 2015-05-18 G. Chincarini , J. Mao , R. Margutti , M. G. Bernardini , C. Guidorzi , F. Pasotti , D. Giannios , M. Della Valle , A. Moretti , P. Romano , P. D'Avanzo , G. Cusumano , P. Giommi

This paper is an attempt to understand the physical processes occurring in different layers of solar atmosphere during a solar flare. For a complete understanding of the flare we must analyze multi-wavelength datasets, as emission at…

Solar and Stellar Astrophysics · Physics 2020-09-30 Shirsh Lata Soni , Radhe Shyam Gupta , Adya Prasad Mishra

Introducing thresholds to analyze time series of emission from the Sun enables a new and simple definition of solar flare events, and their interoccurrence times. Rescaling time by the rate of events, the waiting and quiet time…

Statistical Mechanics · Physics 2007-05-23 Marco Baiesi , Maya Paczuski , Attilio L. Stella

In a recent paper we have calculated the power density spectrum of Gamma-Ray Bursts arising from multiple shocks in a relativistic wind. The wind optical thickness is one of the factors to which the power spectrum is most sensitive,…

Astrophysics · Physics 2009-10-31 M. Spada , A. Panaitescu , P. Meszaros

This paper presents a statistical analysis of Soft X-ray (SXR) flares during the period January 1976 to December 2007 covering solar cycles (SCs) 21, 22, and 23. We have analysed north-south (N-S) and east-west (E-W) asymmetry of SXR at low…

Solar and Stellar Astrophysics · Physics 2015-05-13 Navin Chandra Joshi , Neeraj Singh Bankoti , Seema Pande , Bimal Pande , Kavita Pandey

The hot Local Bubble surrounding the solar neighborhood has been primarily studied through observations of its soft X-ray emission. The measurements were obtained by attributing all of the observed local soft X-rays to the bubble. However,…

Astrophysics · Physics 2009-06-23 Robin L. Shelton

Weak Impulsive Narrowband Quiet Sun Emissions (WINQSEs) are a newly discovered class of radio emission from the solar corona. These emissions are characterized by their extremely impulsive, narrowband and ubiquitous nature. We have…

Solar and Stellar Astrophysics · Physics 2023-08-09 Surajit Mondal , Divya Oberoi , Ayan Biswas , Devojyoti Kansabanik

We report the discovery of an anti-correlation between the soft and the hard X-ray lightcurves of the X-ray binary Aql X-1 when bursting. This behavior may indicate that the corona is cooled by the soft X-ray shower fed by the type-I X-ray…

High Energy Astrophysical Phenomena · Physics 2015-06-17 Yu-Peng Chen , Shu Zhang , Shuang-Nan Zhang , Long Ji , Diego F. Torres , Peter Kretschmar , Jian Li , Jian-Min Wang

Plasma with a temperature close to the chromospheric one is ejected in solar eruptions. Such plasma can occult some part of emission of compact sources in active regions as well as quiet solar areas. Absorption phenomena can be observed in…

Solar and Stellar Astrophysics · Physics 2015-05-20 V. V. Grechnev , I. V. Kuzmenko , I. M. Chertok , A. M. Uralov

The timing of 503 solar flares observed simultaneously in hard X-rays, soft X-rays and H-alpha is analyzed. We investigated the start and the peak time differences in different wavelengths, as well as the differences between the end of the…

Astrophysics · Physics 2015-06-24 A. Veronig , B. Vrsnak , M. Temmer , A. Hanslmeier

We discuss the diagnostics available to study the 5-10 MK plasma in the solar corona, which is key to understanding the heating in the cores of solar active regions. We present several simulated spectra, and show that excellent diagnostics…

Solar and Stellar Astrophysics · Physics 2021-03-11 G. Del Zanna , V. Andretta , P. J. Cargill , A. J. Corso , A. N. Daw , L. Golub , J. A. Klimchuk , H. E. Mason

Observations of radio noise storms can act as sensitive probes of nonthermal electrons produced in small acceleration events in the solar corona. We use data from noise storm episodes observed jointly by the Giant Metrewave Radio Telescope…

Solar and Stellar Astrophysics · Physics 2018-05-22 Tomin James , Prasad Subramanian

Context: The atmosphere of the quiet Sun is controlled by photospheric flows sweeping up concentrations of mixed polarity magnetic field. Along supergranule boundaries and junctions, there is a strong correlation between magnetic flux and…

Astrophysics · Physics 2009-11-13 D. E. Innes , A. Genetelli , R. Attie , H. E. Potts

Proceeding from close association between solar eruptions, flares, shock waves, and CMEs, we analyze relations between bursts at 35 GHz recorded with the Nobeyama Radio Polarimeters during 1990-2012, on the one hand, and solar energetic…

Solar and Stellar Astrophysics · Physics 2015-06-16 V. Grechnev , N. Meshalkina , I. Chertok , V. Kiselev

Solar flares commonly have a hot onset precursor event" (HOPE), detectable from soft X-ray observations. Detecting this requires subtraction of pre-flare fluxes from the non-flaring Sun prior to the event, fitting an isothermal emission…

Solar and Stellar Astrophysics · Physics 2024-07-08 Hugh S. Hudson
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