Switchbacks: statistical properties and deviation from alfvenicity

International audienceSwitchbacks are probably the most prominent features observed by Parker Solar Probe during its first encounter with the Sun. These magnetic structures with reversed polarity have well defined boundaries, higher proton velocity with respect to the surrounding plasma, enhanced wave activity inside the structures and at the boundaries. Their duration varies from a few seconds to tens of minutes. We present an extensive statistical study of their properties, with a particular focus on their boundaries: orientation, type of discontinuity, presence of wave activity, velocity orientation with respect to the boundaries, and Poynting flux. We show that even though they are commonly considered as Alfvénic structures a small percentage of them show slow and fast mode-like correlations between the magnetic field and the proton density