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Related papers: Magnetic Energy Spectra in Active Regions

200 papers

There is a wide range of eruptions in the solar atmosphere which contribute to space weather, including the major explosions of radiation known as flares. To examine pre-event behavior in delta-spot regions, we use here a method based on…

Solar and Stellar Astrophysics · Physics 2019-01-21 Marianna B. Korsos , Shuhong Yang , Robert Erdelyi

Temporal and spectral characteristics of X-ray emission from 60 flares of intensity $\ge$C class observed by Solar X-ray Spectrometer (SOXS) during 2003-2011 are presented. We analyse the X-ray emission observed in four and three energy…

Solar and Stellar Astrophysics · Physics 2018-10-17 Veena Choithani , Rajmal Jain , Arun Kumar Awasthi , Geetanjali Singh , Sneha Chaudhari , Som Kumar Sharma

A solar active region (AR) may produce multiple notable flares during its passage across the solar disk. We investigate successive flares from flare-eruptive active regions, and explore their relationship with solar magnetic parameters. We…

Solar and Stellar Astrophysics · Physics 2023-01-11 Hao Ran , Ying D. Liu , Yang Guo , Rui Wang

The NOAA active region AR 11029 was a small but highly active sunspot region which produced 73 GOES soft X-ray flares. The flares appear to show a departure from the well known power-law frequency-size distribution. Specifically, too few…

Solar and Stellar Astrophysics · Physics 2016-10-28 S. A. Gilchrist , M. S. Wheatland , K. D. Leka

Solar flares are explosions in the solar atmosphere that release intense bursts of short-wavelength radiation and are capable of producing severe space-weather consequences. Flares release free energy built up in coronal fields, which are…

Solar and Stellar Astrophysics · Physics 2020-08-05 Shamik Bhattacharjee , Rasha Alshehhi , Dattaraj B. Dhuri , Shravan M. Hanasoge

A proxy for horizontal electric currents in the solar photosphere was suggested. For a set of evolving active regions (ARs) observed with {\it Solar and Heliospheric Observatory (SOHO)} Michelson Doppler Imager (MDI) in the high resolution…

Astrophysics · Physics 2008-06-11 Valentyna Abramenko

Observational aspects of solar flares relevant to the acceleration process of electrons and protons are reviewed and it is shown that most of these observations can be explained by the interaction with flare plasma of a power law energy…

Astrophysics · Physics 2007-05-23 Vahe Petrosian

Based on several magnetic nonpotentiality parameters obtained from the vector photospheric active region magnetograms obtained with the Solar Magnetic Field Telescope at the Huairou Solar Observing Station over two solar cycles, a machine…

Solar and Stellar Astrophysics · Physics 2013-08-29 Xiao Yang , GangHua Lin , HongQi Zhang , XinJie Mao

Magnetic flux ropes (FRs) are twisted structures appearing on the sun, predominantly in the magnetically concentrated regions. These structures appear as coronal features known as filaments or prominences in H$\alpha$ observations, and as…

Solar and Stellar Astrophysics · Physics 2024-10-04 P. Vemareddy

Energy dissipation is highly intermittent in turbulent plasmas, being localized in coherent structures such as current sheets. The statistical analysis of spatial dissipative structures is an effective approach to studying turbulence. In…

High Energy Astrophysical Phenomena · Physics 2015-09-16 Vladimir Zhdankin , Dmitri A. Uzdensky , Stanislav Boldyrev

We use magnetic field and ion moment data from the MFI and SWE instruments onboard the Wind spacecraft to study the nature of solar wind turbulence at ion-kinetic scales. We analyze the spectral properties of magnetic field fluctuations…

Space Physics · Physics 2018-03-26 Lloyd D. Woodham , Robert T. Wicks , Daniel Verscharen , Christopher J. Owen

We used multi-wavelength high-resolution data from ARIES, THEMIS, and SDO instruments, to analyze a non-standard, C3.3 class flare produced within the active region NOAA 11589 on 2012 October 16. Magnetic flux emergence and cancellation…

Solar and Stellar Astrophysics · Physics 2016-02-22 K. Dalmasse , R. Chandra , B. Schmieder , G. Aulanier

Solar active regions (ARs) are the places hosting the majority of solar eruptions. Studying the evolution and morphological features of ARs is not only of great significance to the understanding of the physical mechanisms of solar…

Solar and Stellar Astrophysics · Physics 2025-02-26 Ruishuo Chen , Wutong Lu , Qi Hao , Yifan Meng , Pengfei Chen , Chenxi Shi

We examine the characteristic properties of photospheric p-modes and sub-photospheric flows of active regions (ARs) observed during the period of 26-31 October 2003. Using ring diagram analysis of Doppler velocity data obtained from the…

Solar and Stellar Astrophysics · Physics 2011-06-22 R. A. Maurya , A. Ambastha

The multi-scaled solar magnetic field consists of two major components: active regions (ARs) and magnetic network. Unraveling the cycle-dependent properties and interrelations of these components is crucial for understanding the evolution…

Solar and Stellar Astrophysics · Physics 2024-06-13 Yukun Luo , Jie Jiang , Ruihui Wang

The coming decade will see the routine use of solar data of unprecedented spatial and spectral resolution, time cadence, and completeness. To capitalize on the new (or soon to be available) facilities such as SDO, ATST and FASR, and the…

We present a numerical analysis of an incompressible decaying magnetohydrodynamic turbulence run on a grid of 1536^3 points. The Taylor Reynolds number at the maximum of dissipation is ~1100, and the initial condition is a superposition of…

Astrophysics · Physics 2009-06-23 P. D. Mininni , A. Pouquet

In recent decades our understanding of solar active regions (ARs) has improved substantially due to observations made with better angular resolution and wider spectral coverage. While prior AR observations have shown that these structures…

Here, we developed a complex network of solar active regions (ARs) to study various local and global properties of the network. The values of the Hurst exponent ($0.8-0.9$) were evaluated by both the detrended fluctuation analysis and the…

Solar and Stellar Astrophysics · Physics 2017-08-23 Farhad Daei , Hossein Safari , Neda Dadashi

Solar flares are widely accepted to be powered by magnetic reconnection that involves complex dynamics in various scales. The flare supra-arcade and loop-top region, directly impacted by fast reconnection downflows, contains a wealth of…

Solar and Stellar Astrophysics · Physics 2025-05-27 Tingyu Gou , Katharine K. Reeves