title: Design of a high-foot high-adiabat ICF capsule for the national ignition facility.
abstract: The National Ignition Campaign's [M. J. Edwards et al., Phys. Plasmas 20, 070501 (2013)] point design implosion has achieved DT neutron yields of 7.5×10(14) neutrons, inferred stagnation pressures of 103 Gbar, and inferred areal densities (ρR) of 0.90  g/cm2 (shot N111215), values that are lower than 1D expectations by factors of 10×, 3.3×, and 1.5×, respectively. In this Letter, we present the design basis for an inertial confinement fusion capsule using an alternate indirect-drive pulse shape that is less sensitive to issues that may be responsible for this lower than expected performance. This new implosion features a higher radiation temperature in the "foot" of the pulse, three-shock pulse shape resulting in an implosion that has less sensitivity to the predicted ionization state of carbon, modestly lower convergence ratio, and significantly lower ablation Rayleigh-Taylor instability growth than that of the NIC point design capsule. The trade-off with this new design is a higher fuel adiabat that limits both fuel compression and theoretical capsule yield. The purpose of designing this capsule is to recover a more ideal one-dimensional implosion that is in closer agreement to simulation predictions. Early experimental results support our assertions since as of this Letter, a high-foot implosion has obtained a record DT yield of 2.4×10(15) neutrons (within ∼70% of 1D simulation) with fuel ρR=0.84  g/cm2 and an estimated ∼1/3 of the yield coming from α-particle self-heating.
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: T R
authors.initials: TR
authors.lastname: Dittrich
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: O A
authors.initials: OA
authors.lastname: Hurricane
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Callahan
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: E L
authors.initials: EL
authors.lastname: Dewald
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: T
authors.initials: T
authors.lastname: Döppner
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: D E
authors.initials: DE
authors.lastname: Hinkel
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: L F
authors.initials: LF
authors.lastname: Berzak Hopkins
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: S
authors.initials: S
authors.lastname: Le Pape
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: T
authors.initials: T
authors.lastname: Ma
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Milovich
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: J C
authors.initials: JC
authors.lastname: Moreno
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: P K
authors.initials: PK
authors.lastname: Patel
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: H-S
authors.initials: HS
authors.lastname: Park
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Remington
authors.affiliation: Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551, USA.
authors.forename: J D
authors.initials: JD
authors.lastname: Salmonson
authors.affiliation: Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
authors.forename: J L
authors.initials: JL
authors.lastname: Kline