title: Fuel gain exceeding unity in an inertially confined fusion implosion.
abstract: Ignition is needed to make fusion energy a viable alternative energy source, but has yet to be achieved. A key step on the way to ignition is to have the energy generated through fusion reactions in an inertially confined fusion plasma exceed the amount of energy deposited into the deuterium-tritium fusion fuel and hotspot during the implosion process, resulting in a fuel gain greater than unity. Here we report the achievement of fusion fuel gains exceeding unity on the US National Ignition Facility using a 'high-foot' implosion method, which is a manipulation of the laser pulse shape in a way that reduces instability in the implosion. These experiments show an order-of-magnitude improvement in yield performance over past deuterium-tritium implosion experiments. We also see a significant contribution to the yield from α-particle self-heating and evidence for the 'bootstrapping' required to accelerate the deuterium-tritium fusion burn to eventually 'run away' and ignite.
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: O A
authors: OA
authors: Hurricane
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: D A
authors: DA
authors: Callahan
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: D T
authors: DT
authors: Casey
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: P M
authors: PM
authors: Celliers
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: C
authors: C
authors: Cerjan
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: E L
authors: EL
authors: Dewald
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: T R
authors: TR
authors: Dittrich
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: T
authors: T
authors: Döppner
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: D E
authors: DE
authors: Hinkel
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: L F
authors: LF
authors: Berzak Hopkins
authors: Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors: J L
authors: JL
authors: Kline
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: S
authors: S
authors: Le Pape
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: T
authors: T
authors: Ma
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: A G
authors: AG
authors: MacPhee
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: J L
authors: JL
authors: Milovich
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: A
authors: A
authors: Pak
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: H-S
authors: HS
authors: Park
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: P K
authors: PK
authors: Patel
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: B A
authors: BA
authors: Remington
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: J D
authors: JD
authors: Salmonson
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: P T
authors: PT
authors: Springer
authors: Lawrence Livermore National Laboratory, PO Box 808, Livermore, California 94551, USA.
authors: R
authors: R
authors: Tommasini