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Quiescent prominences host a diverse range of flows, includingRayleigh-Taylor instability driven upflows and impulsive downflows, and so itis no surprise that turbulent motions also exist. As prominences are believedto have a mean horizontal guide field, investigating any turbulence they hostcould shed light on the nature of MHD turbulence in a wide range ofastrophysical systems. In this paper we have investigated the nature of theturbulent prominence motions using structure function analysis on the velocityincrements estimated from H$\alpha$ Dopplergrams constructed with observationaldata from Hinode SOT. The pdf of the velocity increments shows that as we lookat increasingly small spatial separations the distribution displays greaterdeparture from a reference Gaussian distribution, hinting at intermittency inthe velocity field. Analysis of the even order structure functions for both thehorizontal and vertical separations showed the existence of two distinctregions displaying different exponents of the power law with the break in thepower law at approximately 2000km. We hypothesise this to be a result ofinternal turbulence excited in the prominence by the dynamic flows of thesystem found at this spatial scale. We found that the scaling exponents of thep-th order structure functions for these two regions generally followed the p/2(smaller scales) and p/4 (larger scales) laws that are the same as thosepredicted for weak MHD turbulence and Kraichnan-Iroshnikov turbulencerespectively. However, the existence of the p/4 scaling at larger scales thanthe p/2 scaling is inconsistent with the increasing nonlinearity expected inMHD turbulence. Estimating the heating from the turbulent energy dissipationshowed that this turbulent heating would be very inefficient, but that the massdiffusion through turbulence driven reconnection was of the order of$10^{10}$cm$^2$/s.

Investigating prominence turbulence with Hinode SOT Dopplergrams