Nonaxisymmetric magnetic field generation in rapidly rotating late-type stars
Nonaxisymmetric magnetic field generation in rapidly rotating late-type stars
复制标题
DOI：
10.1051/0004-6361:20041710
复制
发表时间：
2005-03
影响因子：
6.5
通讯作者：
D. Moss
中科院分区：
文献类型：
--
作者：
D. Moss
Recently the discovery of the “flip-flop” phenomenon, by which a predominant “active” longitude jumps by about $180^\circ$, on several rapidly rotating late-type stars has directed attention to the issues surrounding the presence of large-scale nonaxisymmetric magnetic fields in these objects. Here we study nonlinear mean field dynamo models with quasi-cylindrical rotation laws, acting in spherical shells. Stable nonaxisymmetric magnetic fields are found to be generated for a range of parameters and, for certain of these models, jumps in a measure plausibly related to the position of active longitudes are found to occur. In general, nonaxisymmetric fields appear to be easier to generate in thinner dynamo-active regions. However, flip-flops appear to be stronger for intermediate thicknesses of the dynamo-active shells.
