Signatures of Intermittent Turbulence in Hinode Quiet Sun Photosphere Signatures of Intermittent Turbulence in Hinode Quiet Sun Photosphere Valentina Abramenko, Big Bear Solar Observatory, USA, www.bbso.njit.edu/~avi Plasma turbulence is ubiquitous in astrophysics in general and in the solar photosphere, in particular. It is a fundamental physical process that plays an important role in the near-surface turbulent dynamo and plasma heating through dissipation. Turbulence acquires intermittent nature when extremely high fluctuations (in both temporal and spatial domains) become not rare and they thus determine the energy release dynamics: significant contribution to the traditional turbulent energy cascade appears in the intermittent medium. We estimated signatures of intermittent turbulence in the quiet sun photosphere utilizing Hinode/SOT data. We found that at scales below 1 Mm the QS structures are highly intermittent, which open possibilities for enhanced energy release dynamics at small scales. What is the Intermittency A turbulent medium can display a property of intermittency: a tendency to concentrate into strong blobs (sometimes in a shape of sheets , or tubes) of all scales intermittent with vast areas of low intensity, a presence of extremely strong fluctuations and a burst-like behavior in time evolution. Intermittent structure is a multufractal. Generally, intermittency and multifractality are two different terms for the same phenomenon. Historically, the former term (intermittency) is usually applied to time series Analysis, whereas the later one (multifractality) is used for spatial objects (Takayasu, 1989; Frisch, 1995). In scale intervals, where How to measure the degree of intermittency r Structure functions were first introduced by Kolmogorov (1941). The ratio of the squared second structure function, S2( r ) (red), over the forth structure function, S4( r ) (blue), gives us the Filling Factor, f(r ) . The Filling Factor does not depend on the scale, r, For non-intermittent (or, monofractal) structures and time series. For intermittent structures, the filling factor decreases as the scale decreases. For non-intermittent structures (like a Gaussian process) the filling factor does not depend on scale. The steeper the slope of decrease, the more intermittent the structure is. In the multifractal terminology, the steeper the filling factor means the more complex multifractal, which is a superposition of a set of monofractals. For example, in the solar wind turbulence, the presence of interminnency implies the presence of magnetic field discontinuities, shocks and current sheets of various scales. All these phenomena contribute significantly into the energy release dynamics, along with the usual turbulent cascade. Intermittency of the magnetic field from SOHO/MDI high resolution data We first applied the filling factor technique to magnetograms from SOHO/MDI obtained in the high resolution mode. Areas of three types we analyzed: Active Region (AR) area ( red), Plage area (green) and two areas in the quiet sun, which were mostly located inside small coronal holes (blue and turquoise). Middle figure – the filling factor function (linear axes) for the AR data. The interval of decreasing filling factor is well pronounced: 5 – 30 Mm. Below 5 Mm the filling factor increases, which is caused by the noise influence and poor resolution of the magnetogram. Right figure – the filling factor as a function of a spatial scale (double logarithmic plot) for three types of magnetic structures. For all of then, the filling factor function starts to increase at small scales as a result of insufficient data resolution. Note that while both the AR and the plage data display an intermittent nature of the magnetic field at scales above 2 Mm, the quiet sun data seems to display no intermittency at these scales. If we ignore the noise-related hooks and contunuously extend the AR and plage curves (dotted curve with the arrow) below the base lane of the quiet sun plateu, we may conclude that at scales below 1000 km one may expect the decreasing behavior of the filling factor in the quiet sun areas, i.e., the intermittent property of the QS magnetic field. Quiet sun