Recent observations have demonstrated that waves capable of carrying large amounts of energy are ubiquitous throughout the solar corona. However, the question of how this wave energy is dissipated (on which timescales and length scales) and released into the plasma remains largely unanswered. Both analytic and numerical models have previously shown that Alfvénic turbulence may play a key role not only in the generation of the fast solar wind, but in the heating of coronal loops. In an effort to bridge the gap between theory and observations, we expand on a recent study by analyzing 37 clearly isolated coronal loops using data from the Coronal Multi-channel Polarimeter instrument. We observe Alfvénic perturbations with phase speeds which range from 250 to 750 km s–1 and periods from 140 to 270 s for the chosen loops. While excesses of high-frequency wave power are observed near the apex of some loops (tentatively supporting the onset of Alfvénic turbulence), we show that this excess depends on loop length and the wavelength of the observed oscillations. In deriving a proportional relationship between the loop length/wavelength ratio and the enhanced wave power at the loop apex, and from the analysis of the line widths associated with these loops, our findings are supportive of the existence of Alfvénic turbulence in coronal loops.
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机译：最近的观察表明，在整个日冕中，能够携带大量能量的波无处不在。但是，如何消散波能（在哪个时间尺度和长度尺度上）并释放到等离子体中的问题在很大程度上仍未解决。以前的解析模型和数值模型都表明，Alfvénic湍流不仅在快速太阳风的产生中，而且在日冕环的加热中都可能起关键作用。为了弥合理论与观察之间的差距，我们通过使用日冕多通道旋光仪的数据分析了37个清晰孤立的日冕环，从而扩展了最近的一项研究。对于选定的环路，我们观察到Alfvénic扰动，其相速范围从250到750 km s-1，周期从140到270 s。虽然在某些环路的顶点附近观察到了高频波功率的过剩（暂时支持Alfvénic湍流的发生），但我们表明，这种过剩取决于环路的长度和观察到的振荡的波长。在推导环路长度/波长比与环路顶点处增强的波功率之间的比例关系时，并根据与这些环路相关的线宽的分析，我们的发现支持冠状环路中存在Alfvénic湍流。
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