論文

2011年4月

Dependence of the Magnetic Energy of Solar Active Regions on the Twist Intensity of the Initial Flux Tubes

PUBLICATIONS OF THE ASTRONOMICAL SOCIETY OF JAPAN
  • Shin Toriumi
  • ,
  • Takehiro Miyagoshi
  • ,
  • Takaaki Yokoyama
  • ,
  • Hiroaki Isobe
  • ,
  • Kazunari Shibata

63
2
開始ページ
407
終了ページ
415
記述言語
英語
掲載種別
研究論文(学術雑誌)
DOI
10.1093/pasj/63.2.407
出版者・発行元
OXFORD UNIV PRESS

We present a series of numerical experiments that model the evolution of magnetic flux tubes with a different amount of initial twist. As a result of calculations, tightly twisted tubes reveal a rapid two-step emergence to the atmosphere with a slight slowdown at the surface, while weakly twisted tubes show a slow two-step emergence waiting longer the secondary instability to be triggered. This picture of the two-step emergence is highly consistent with recent observations. These tubes show multiple magnetic domes above the surface, indicating that the secondary emergence is caused by an interchange mode of magnetic buoyancy instability. In the case of the weakest twist, the tube exhibits an elongated photospheric structure, and never rises into the corona. The formation of the photospheric structure is due to an inward magnetic tension force of the azimuthal field component of the rising flux tube (i.e., tube's twist). When the twist is weak, the azimuthal field cannot hold the tube's coherency, and the tube extends laterally at the subadiabatic surface. In addition, we newly found that the total magnetic energy measured above the surface depends on the initial twist. Strong twist tubes follow the initial relation between the twist and the magnetic energy, while weak twist tubes deviate from this relation, because these tubes store their magnetic energy in the photospheric structure.

リンク情報
DOI
https://doi.org/10.1093/pasj/63.2.407
Web of Science
https://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=JSTA_CEL&SrcApp=J_Gate_JST&DestLinkType=FullRecord&KeyUT=WOS:000291075900012&DestApp=WOS_CPL
ID情報
  • DOI : 10.1093/pasj/63.2.407
  • ISSN : 0004-6264
  • eISSN : 2053-051X
  • Web of Science ID : WOS:000291075900012

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