1 Confinement improvement and fuelling Highly peaked electron density profiles has been found to exhibit significantly improved energy confinement relative to more standard Tokamak operation. A famous expmple of supershots with peaked-density profiles initiated and maintained by central- 1 Confinement improvement and fuelling Highly peaked electron density profiles has been found to exhibit significantly improved energy confinement relative to more standard Tokamak operation. A famous expmple of supershots with peaked-density profiles initiated and maintained by central-