Paper ’Seeding of Self-Modulation Instability of a Long Electron Bunch in a Plasma’ by Y. Fang et al was published in Physical Review Letters. It describes a series of experiments performed in the Accelerator Test Facility (ATF) at Brookhaven National Laboratory demonstrating the seeding of the self-modulation instability by long bunches with sharp rise density profiles. This work supports the concept of similar experiments in the future, e.g. Self-Modulation Instability (SMI) experiments using long bunches of relativistic protons. More information can be read here.