{'fraction_non_alphanumeric': 0.02258064516129032, 'fraction_numerical': 0.0, 'mean_word_length': 6.305882352941176, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Magnetic islands formed due to the Kelvin‐Helmholtz instability in the outflow region of collisionless magnetic reconnection

We carry out large‐scale particle‐in‐cell kinetic simulations to demonstrate that a super‐Alfvénic electron shear flow across the current layer can be spontaneously generated in the outflow region of magnetic reconnection, which is unstable to the electron Kelvin‐Helmholtz (K‐H) instability. The resulted K‐H vortex structures continuously drive the secondary magnetic reconnection and formation of secondary magnetic islands, which leads to strong electron energization in the outflow region.