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Related papers: Flows and Waves in Braided Solar Coronal Magnetic …

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Aims: Our aim is to investigate the resistive relaxation of a magnetic loop that contains braided magnetic flux but no net current or helicity. The loop is subject to line-tied boundary conditions. We investigate the dynamical processes…

Solar and Stellar Astrophysics · Physics 2015-05-18 D. I. Pontin , A. L. Wilmot-Smith , G. Hornig , K. Galsgaard

Local helioseismology provides a unique opportunity to investigate the subsurface structure and dynamics of active regions and their effect on the large-scale flows and global circulation of the Sun. We use measurements of plasma flows in…

Solar and Stellar Astrophysics · Physics 2016-07-19 Alexander G. Kosovichev , Junwei Zhao , Stathis Ilonidis

Quasi-periodic disturbances of emission-line parameters are frequently observed in the corona. These disturbances propagate upward along the magnetic field with speeds $\sim100~\rm{km~s}^{-1}$. This phenomenon has been interpreted as…

Solar and Stellar Astrophysics · Physics 2016-07-06 Wenzhi Ruan , Jiansen He , Lei Zhang , Christian Vocks , Eckart Marsch , Chuanyi Tu , Hardi Peter , Linghua Wang

We explore the general properties of near-surface flows around solar active regions. Helioseismic holography is applied to HMI Dopplergrams yielding nearly 5000 flow measurements of 336 unique active regions observed by the Solar Dynamics…

Solar and Stellar Astrophysics · Physics 2019-03-20 D. C. Braun

Near-surface flows measured by the ring-diagram technique of local helioseismology show structures that persist over multiple rotations. We examine these phenomena using data from the {\em Global Oscillation Network Group} (GONG) and the…

Solar and Stellar Astrophysics · Physics 2015-08-19 R. Howe , R. W. Komm , D. Baker , L. Harra , L. van Driel-Gesztelyi , R. S. Bogart

Quasi-periodic wiggles of microwave zebra pattern structures with period range from about 0.5 s to 1.5 s are found in a X-class solar flare on 2006 December 13 at the 2.6-3.8 GHz with the Chinese Solar Broadband Radio Spectrometer…

Solar and Stellar Astrophysics · Physics 2015-06-17 Sijie Yu , V. M. Nakariakov , L. A. Selzer , Baolin Tan , Yihua Yan

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

We present an observational study of a quasi-periodic fast propagating (QFP) magnetosonic wave on 2012, April 23. The multiple wave trains were observed along an active region open loop system which has a divergence geometry. The wave…

Solar and Stellar Astrophysics · Physics 2015-06-16 Y. D. Shen , Y. Liu , J. T. Su , H. Li , X. F. Zhang , Z. J. Tian , R. J. Zhao , A. Elmhamdi

One of the major discoveries of Hinode's Extreme-ultraviolet Imaging Spectrometer (EIS) is the presence of upflows at the edges of active regions. As active regions are magnetically connected to the large-scale field of the corona, these…

Numerous observations have revealed that power-law distributions are ubiquitous in energetic solar processes. Hard X-rays, soft X-rays, extreme ultraviolet radiation, and radio waves all display power-law frequency distributions. Since…

Solar and Stellar Astrophysics · Physics 2018-02-14 Kalman J. Knizhnik , Vadim M. Uritsky , James A. Klimchuk , C. Richard DeVore

Drifting pulsation structures (DPSs) are considered to be radio signatures of the plasmoids formed during magnetic reconnection in the impulsive phase of solar flares. In the present paper we analyze oscillations and waves in seven examples…

Solar and Stellar Astrophysics · Physics 2018-04-25 M. Karlicky , J. Rybak , M. Barta

The recent launch of the High resolution Coronal imager (Hi-C) provided a unique opportunity to study the EUV corona with unprecedented spatial resolution. We utilize these observations to investigate the properties of low frequency (50-200…

Solar and Stellar Astrophysics · Physics 2013-06-28 R. J. Morton , J. A. McLaughlin

We analyse the signature and origin of transient structures embedded in the slow solar wind, and observed by the Wide-Field Imager for Parker Solar Probe (WISPR) during its first ten passages close to the Sun. WISPR provides a new in-depth…

Solar and Stellar Astrophysics · Physics 2023-09-13 Nicolas Poirier , Victor Réville , Alexis P. Rouillard , Athanasios Kouloumvakos , Emeline Valette

Using one-arcsecond-slit scan observations from the Hinode/EUV Imaging Spectrometer (EIS) on 05 February 2007, we find the plasma outflows in the open and expanding coronal funnels at the eastern boundary of AR 10940. The Doppler velocity…

Solar and Stellar Astrophysics · Physics 2015-06-22 A. K. Srivastava , P. Konkol , K. Murawski , B. N. Dwivedi , A. Mohan

We describe the characteristics and evolution of the magnetic field and chromospheric emission in an active region core observed by the Solar Optical Telescope on Hinode. Consistent with previous studies, we find that the moss is unipolar,…

Solar and Stellar Astrophysics · Physics 2015-05-19 David H. Brooks , Harry P. Warren , Amy R. Winebarger

Quasi-periodic, propagating fast mode magnetosonic waves in the corona were difficult to observe in the past due to relatively low instrument cadences. We report here evidence of such waves directly imaged in EUV by the new SDO AIA…

We observe intensity oscillations along coronal fan loops associated with the active region AR 11428. The intensity oscillations were triggered by blast waves which were generated due to X-class flares in the distant active region AR 11429.…

Solar and Stellar Astrophysics · Physics 2017-09-20 V. Pant , A. Tiwari , D. Yuan , D. Banerjee

Quasi-periodic propagating intensity disturbances have been observed in large coronal loops in EUV images over a decade, and are widely accepted to be slow magnetosonic waves. However, spectroscopic observations from Hinode/EIS revealed…

Solar and Stellar Astrophysics · Physics 2015-11-04 X. Fang , D. Yuan , T. Van Doorsselaere , R. Keppens , C. Xia

The analysis of multiwavelength properties of propagating disturbances (PDs) using Hinode/EIS observations is presented. Quasi-periodic PDs were mostly interpreted as slow magnetoacoustic waves in early studies, but recently suggested to be…

Solar and Stellar Astrophysics · Physics 2015-01-19 Tongjiang Wang , Leon Ofman , Joseph M. Davila

Earlier studies using extreme-ultraviolet images and line-of-sight magnetograms from the Solar Dynamics Observatory (SDO) have suggested that active region (AR) plages and strong network concentrations often have small, looplike features…

Solar and Stellar Astrophysics · Physics 2021-04-15 Y. -M. Wang , I. Ugarte-Urra , J. W. Reep