Magnetic Fields Around Stars Can Suppress Plasma Eruptions, Technion Study Finds

A new study from Technion researchers and European colleagues provides the first experimental evidence that strong magnetic fields around stars can completely suppress powerful plasma eruptions known as coronal mass ejections (CMEs), potentially explaining why these events are rare on other stars. The experiments, published in Physical Review Letters, combined laser plasma tests, astrophysical simulations, and 3D magnetohydrodynamic models. They showed a clear transition: weak magnetic fields allowed plasma flows to expand freely, while stronger fields made flows unstable, break apart, and halt entirely due to kink instabilities. The findings match astrophysical predictions, indicating a magnetic field of about 100 gauss can confine such eruptions and prevent their escape into space. This helps solve a long-standing mystery about why giant eruptions routinely seen on the Sun are nearly absent around other stars.