Current Sheets and Magnetic Reconnection statistics by Solar Orbiter at few to tens of Ion Inertial Lengths II: Conditions for Reconnection, and Current Sheet Planarity

Abstract

We present a statistical study of magnetic reconnection and current sheet (CS) properties at scales from the ion inertial length ($δ_i$), up to 86.4 $δ_i$. We analyze 103 hours of high-cadence (4 samples/s) in-situ Solar Orbiter ion data, collected from July 2020 to September 2022, which correspond mainly to slow and Alfvénic solar wind. We applied an automatic detection algorithm to find CSs of thicknesses near and above the ion inertial length ($δ_i$), and classify them as Alfvénic or reconnecting. The orientation of the CSs is consistent with an isotropic distribution of the discontinuities. The median ratio of reconnection jet velocity to theoretical outflow velocity is 0.71. We find that the diamagnetic drift reconnection suppression mechanism has no impact on the cataloged CSs, due to the symmetry of their upstream conditions. We find that a flow shear in the reconnection direction suppresses magnetic reconnection, and it is consistently greater for Alfvénic than for reconnecting CSs. Flow shear in the guide-field direction is too small to suppress magnetic reconnection in ion scale solar wind CSs.