Uncertainties of the solar wind in-situ velocity measurements

Abstract

We study spectral features of Alfvénic turbulence in fast solar wind. We propose a general, instrument independent method to estimate the uncertainty in velocity fluctuations obtained by in-situ satellite observations in the solar wind. We show that when the measurement uncertainties of the velocity fluctuations are taken into account the less energetic Elsasser spectrum obeys a unique power law scaling throughout the inertial range as prevailing theories of magnetohydrodynamic turbulence predict.