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Related papers: Short-term evolution of coronal hole boundaries

200 papers

I discuss the results of simplified three dimensional magnetohydrodynamic simulations of the boundary layer between a disc and a non-rotating, unmagnetized star. Strong magnetic fields, possibly approaching equipartition with the thermal…

Astrophysics · Physics 2007-05-23 Philip J. Armitage

There is evidence for coronal plasma flows to break down into fragments and to be laminar. We investigate this effect by modeling flows confined along magnetic channels. We consider a full MHD model of a solar atmosphere box with a dipole…

Solar and Stellar Astrophysics · Physics 2017-12-27 A. Petralia , F. Reale , P. Testa

Oscillatory magnetic reconnection is a periodic magnetic reconnection process, during which the current sheet's orientation and the magnetic connections change periodically. This periodic variation is generally considered to originate from…

Solar and Stellar Astrophysics · Physics 2025-06-02 Yifu Wang , Lei Ni , Guanchong Cheng , Jialiang Hu , Yuhao Chen , Abdullah Zafar

We use full-disk, SOHO/EIT 195 $\AA$ calibrated images to measure latitudinal and day to day variations of area and average photon fluxes of the near equatorial coronal holes. In addition, energy emitted by the coronal holes with their…

Solar and Stellar Astrophysics · Physics 2022-04-12 K. M. Hiremath , Manjunath Hegde

This paper presents results of comparison between observations of coronal holes in the UV (SOHO EIT) and microwave emission (17, 5.7 GHz, 327 and 150.9 MHz, NoRH, SSRT and Nancy radioheliographs), and solar wind parameters, according to the…

Solar and Stellar Astrophysics · Physics 2015-05-20 D. Prosovetsky , I. Myagkova

We present a new model for time evolution of fast magnetic reconnection in free space, which is characterized by self-similarity. Reconnection triggered by locally enhanced resistivity assumed at the center of the current sheet can…

Astrophysics · Physics 2009-10-31 S. Nitta , S. Tanuma , K. Shibata , K. Maezawa

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

On 2015 January 6-7, an interplanetary coronal mass ejection (ICME) was observed at L1. This event, which can be associated with a weak and slow coronal mass ejection, allows us to discuss on the differences between the boundaries of the…

Solar and Stellar Astrophysics · Physics 2016-09-06 C. Cid , J. Palacios , E. Saiz , A. Guerrero

A new method for automated coronal loop tracking, in both spatial and temporal domains, is presented. Applying this technique to TRACE data, obtained using the 171 Angstrom filter on 1998 July 14, we detect a coronal loop undergoing a 270s…

Astrophysics · Physics 2009-11-13 D. B. Jess , M. Mathioudakis , R. Erdelyi , G. Verth , R. T. J. McAteer , F. P. Keenan

Fast magnetic reconnection is defined by the topology of the magnetic field lines changing on a timescale that is approximately an order of magnitude longer than the topology-conserving ideal-evolution timescale. Fast reconnection is an…

Plasma Physics · Physics 2022-05-18 Allen H Boozer

The heating of the solar corona and the puzzle of the slender high reaching magnetic loops seen in observations from the Transition Region And Coronal Explorer(TRACE) has been investigated through 3D numerical simulations, and found to be…

Astrophysics · Physics 2007-05-23 Boris V. Gudiksen , Aake Nordlund

Solar flares are driven by release of free magnetic energy and often associated with restructurization of the magnetic field topology. Yet, observations of evolving magnetic field in the flaring volume are limited to very few cases…

Solar and Stellar Astrophysics · Physics 2026-02-18 Gregory D. Fleishman , Tatyana Kaltman , Sijie Yu

The solar magnetic field is the primary agent that drives solar activity and couples the Sun to the Heliosphere. Although the details of this coupling depend on the quantitative properties of the field, many important aspects of the corona…

Astrophysics · Physics 2009-11-13 S. K. Antiochos , C. R. DeVore , J. T. Karpen , Z. Mikic

Coronal jets and bright points occur prolifically in predominantly unipolar magnetic regions, such as coronal holes, where they appear above minority-polarity intrusions. Intermittent low-level reconnection and explosive,…

Solar and Stellar Astrophysics · Physics 2018-09-19 Peter F. Wyper , C. Richard DeVore , Judy T. Karpen , Spiro K. Antiochos , Anthony R. Yeates

Coronal holes are the darkest and least active regions of the Sun, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the high-speed…

Solar and Stellar Astrophysics · Physics 2015-05-14 Steven R. Cranmer

During eruptive flares, vector magnetograms show increasing horizontal magnetic field and downward Lorentz force in the Sun's photosphere around the polarity-inversion line. Such behavior has often been associated with the implosion…

Solar and Stellar Astrophysics · Physics 2019-06-05 Krzysztof Barczynski , Guillaume Aulanier , Sophie Masson , Michael S. Wheatland

The interaction between interplanetary small-scale magnetic flux ropes and the magnetic field in the ambient solar wind is an important topic to understand- ing the evolution of magnetic structures in the heliosphere. Through a survey of…

Solar and Stellar Astrophysics · Physics 2015-05-19 Hui Tian , Shuo Yao , Qiugang Zong , Jiansen He , Yu Qi

Coronal dimmings, localized regions of reduced emission in the EUV and soft X-rays, are interpreted as density depletions due to mass loss during the CME expansion. They contain crucial information on the early evolution of CMEs low in the…

Solar and Stellar Astrophysics · Physics 2018-08-29 Karin Dissauer , Astrid M. Veronig , Manuela Temmer , Tatiana Podladchikova , Kamalam Vanninathan

Coronal holes are the coolest and darkest regions of the solar atmosphere, as observed both on the solar disk and above the solar limb. Coronal holes are associated with rapidly expanding open magnetic fields and the acceleration of the…

Solar and Stellar Astrophysics · Physics 2011-09-21 D. Banerjee , G. R. Gupta , L. Teriaca

The observed solar activity is believed to be driven by the dissipation of nonpotential magnetic energy injected into the corona by dynamic processes in the photosphere. The enormous range of scales involved in the interaction makes it…

Solar and Stellar Astrophysics · Physics 2015-06-12 Vadim M. Uritsky , Joseph M. Davila , Leon Ofman , Aaron J. Coyner