Testing the effects of expansion on solar wind turbulence

摘要: We present a multi-spacecraft approach to test the predictions of recent studies on effect solar wind expansion radial spectral, variance, and local 3D anisotropies turbulence. found that small scales (5000?10,000 km) power levels B-trace structure functions do not depend sampling direction with respect suggesting this scale is possibly due fast turbulent timescales. On larger (110?135 R E ), fluctuations magnetic field component are reduced by ~20% compared transverse (perpendicular radial) ones, which could be confining into plane perpendicular radial. For spectral anisotropy, showed dependence The anisotropy in when increments taken radial, an expansion.