We present a detailed study of intermittency in the velocity and magnetic field fluctuations of compressible Hall-magnetohydrodynamic turbulence with an external guide field. To solve the equations numerically, a reduced model valid when a strong guide field is present is used. Different values for the ion skin depth are considered in the simulations. The resulting data is analyzed computing field increments in several directions perpendicular to the guide field, and building structure functions and probability density functions. In the magnetohydrodynamic limit we recover the usual results with the magnetic field being more intermittent than the velocity field. In the presence of the Hall effect, field fluctuations at scales smaller than the ion skin depth show a substantial decrease in the level of intermittency, with close to monofractal scaling.Comment: 10 pages, 8 figure

Clear Air Turbulence (CAT) occurs in the upper troposphere and lower stratosphere (UTLS) and is an unexpected, dangerous, and often elusive phenomenon (Gultepe et al., 2019;Mazon et al., 2018). Over the past 50 yr, the study and characterization of aviation-related CAT events has gained importance (Dutton & Panofsky, 1970;Ellrod et al., 2003;Gary et al., 1992), and a large number of injuries to passengers and crew from CAT are presumed (Sharman & Pearson, 2017). Regardless of the particular aircraft, CAT is recognized as in-flight bumps directly caused by small-scale turbulent eddies in the free atmosphere within cloud-free airflow or in stratiform clouds (J. H. Kim & Chun, 2010). In geophysical fluid dynamics and atmospheric sciences, CAT is considered to be a patchy turbulent eddy motion that arises as an expression of Kelvin-Helmholtz instabilities, that is, generated primarily by shear (Ellrod et al., 2003). Observational studies indicate that this shear is mainly