Research of generation mechanisms and dynamics of solar magnetic fields

2015 Fiscal Year Final Research Report

• Project/Area Number: 23340042
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Astronomy
• Research Institution: The University of Tokyo
• Principal Investigator: YOKOYAMA Takaaki 東京大学, 理学(系)研究科(研究院), 准教授 (00311184)
• Research Collaborator: TORIUMI Shin ; HOTTA Hideyuki ; IIJIMA Haruhisa ; KANEKO Takafumi ; WANG Shuoyang ; MATSUI Yuki ; KITAGAWA Naomasa
• Project Period (FY): 2011-04-01 – 2015-03-31
• Keywords: 天文 / 太陽物理学 / プラズマ

Outline of Final Research Achievements

We studied the generation mechanisms and the dynamics of the solar magnetic fields by means of the numerical simulations. By the computations with our own code including the reduced-speed-of-sound technique on the RIKEN ``K''-system, we succeeded to obtain a new knowledge on the global-scale solar magnetic convection in the solar interior. The small-scale downflows generated in the near-surface layer penetrate into deeper layers and excite small-scale turbulence. A small-scale dynamo action is generated there. We also clarify the mechanisms to maintain the near surface shear layer in the sun, which was a remained puzzle of the solar rotation profile. It is maintained by the balance between the transports of angular momentum by the turbulence and the meridional circulation. In addition to these, we found that there is a strong feed-back from the magnetic field generated by the small-scale dynamo by the turbulence toward the large-scale thermal transport.

Free Research Field

天文学