Super-elastic Collision of Large-scale Magnetized Plasmoids in The   Heliosphere
  Super-elastic collision is an abnormal collisional process, in which some particular mechanisms cause the kinetic energy of the system increasing. Most studies in this aspect focus on solid-like objects, but they rarely consider gases or liquids, as the collision of the latter is primarily a mixing process. With cross-field diffusion being effectively prohibited, magnetized plasmoids are different from ordinary gases. But it remains unclear how they act during a collision. Here we present the global picture of a unique collision between two coronal mass ejections in the heliosphere, which are the largest magnetized plasmoids erupting from the Sun. Our analysis for the first time reveals that these two magnetized plasmoids collided like solid-like objects with a 73% likelihood of being super-elastic. Their total kinetic energy surprisingly increased by about 6.6% through the collision, which significantly influenced the dynamics of the plasmoids. 
Chenglong Shen, Yuming Wang, Shui Wang, Ying Liu, Rui Liu, Angelos   Vourlidas, Bin Miao, Pinzhong Ye, Jiajia Liu, Zhenjun Zhou
astro-ph.SR physics.plasm-ph physics.space-ph