arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1609.01199astro-ph.SR
收藏

向活动区的流入和太阳周期的调制:参数研究

Inflows towards active regions and the modulation of the solar cycle: a parameter study

David Martin-Belda, Robert H. Cameron

摘要:

目标:我们的目标是调查如何收敛流向活跃地区的影响表面传输的磁通量,以及它们对太阳的极向场的产生的影响。流入构成了一个潜在的非线性机制的饱和的全球发电机,并可能有助于调制的太阳活动周期在Babcock-Leighton框架。方法:我们建立了一个表面通量传输代码,将参数化模型的流入和运行模拟跨越几个周期。我们进行了参数研究,以评估流入的强度和范围如何影响全球偶极子场的建立。我们还进行了模拟与不同水平的活动,以调查的潜在作用的流入饱和的全球发电机。结果如下:我们发现,相邻的活动区域的相互作用,可以导致偶尔形成的单极性磁通量团块与观测不一致。我们提出,在高磁场强度的地区,作为一个合理的机制,防止这种通量聚集的孔隙所造成的变暗。我们发现,流入减少了一个$\sim30\,\%$的轴向偶极矩的幅度,相对于一个没有流入的情况。较强(较弱)的流入导致较大(较小)的轴向偶极矩的减少。产生的轴向偶极子的相对振幅是约$9\%$后,非常弱的周期比非常强的周期。这支持流入作为一种非线性机制,能够饱和的全球发电机和促进巴布科克-莱顿框架内的太阳周期的调制。

英文摘要:

Aims: We aim to investigate how converging flows towards active regions affect the surface transport of magnetic flux, as well as their impact on the generation of the Sun's poloidal field. The inflows constitute a potential non-linear mechanism for the saturation of the global dynamo and may contribute to the modulation of the solar cycle in the Babcock-Leighton framework. Methods: We build a surface flux transport code incorporating a parametrized model of the inflows and run simulations spanning several cycles. We carry out a parameter study to assess how the strength and extension of the inflows affect the build-up of the global dipole field. We also perform simulations with different levels of activity to investigate the potential role of the inflows in the saturation of the global dynamo. Results: We find that the interaction of neighbouring active regions can lead to the occasional formation of single-polarity magnetic flux clumps inconsistent with observations. We propose the darkening caused by pores in areas of high magnetic field strength as a plausible mechanism preventing this flux-clumping. We find that inflows decrease the amplitude of the axial dipole moment by a $\sim30\,\%$, relative to a no-inflows scenario. Stronger (weaker) inflows lead to larger (smaller) reductions of the axial dipole moment. The relative amplitude of the generated axial dipole is about $9\%$ larger after very weak cycles than after very strong cycles. This supports the inflows as a non-linear mechanism capable of saturating the global dynamo and contributing to the modulation of the solar cycle within the Babcock-Leighton framework.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑