标题： 小尺度太阳表层发电机 显示英文标题

标题： The small-scale solar surface dynamo

摘要： 考虑到现有的数值和实验室实验，以及MURaM模拟中的小尺度发电机与Hinode观测的比较，小尺度太阳表面发电机的存在是可能的。 我们发现从Stokes-V磁图中观察到的概率分布函数（PDF）与实际垂直磁场强度的单调PDF一致。 从Hinode SP观测中得到的垂直通量密度的抵消函数在长度尺度上遵循自相似幂律，覆盖两个数量级，直到约200公里的分辨率极限。 这提供了观测证据，表明光球中的磁结构尺度至少可以延伸到20公里。 从幂律中，我们确定了真实宁静太阳平均垂直无符号通量密度的下限约为43 G，这与我们基于数值的估计一致，即由于抵消作用，在200公里的分辨率下，80%或更多的垂直无符号通量对Stokes-V观测来说是不可见的。 我们的估计显著减少了基于塞曼效应和汉勒效应的估计之间的数量级差异。 显示英文摘要

摘要： The existence of a turbulent small-scale solar surface dynamo is likely, considering existing numerical and laboratory experiments, as well as comparisons of a small-scale dynamo in MURaM simulations with Hinode observations. We find the observed peaked probability distribution function (PDF) from Stokes-V magnetograms is consistent with a monotonic PDF of the actual vertical field strength. The cancellation function of the vertical flux density from a Hinode SP observation is found to follow a self-similar power law over two decades in length scales down to the ~200 km resolution limit. This provides observational evidence that the scales of magnetic structuring in the photosphere extend at least down to 20 km. From the power law, we determine a lower bound for the true quiet-Sun mean vertical unsigned flux density of ~43 G, consistent with our numerically-based estimates that 80% or more of the vertical unsigned flux should be invisible to Stokes-V observations at a resolution of 200 km owing to cancellation. Our estimates significantly reduce the order-of-magnitude discrepancy between Zeeman- and Hanle-based estimates.