The design of the optical Thomson scattering diagnostic for the National Ignition Facility

P S Datte; J S Ross; D H Froula; K D Daub; J Galbraith; S Glenzer; B Hatch; J Katz; J Kilkenny; O Landen; D Manha; A M Manuel; W Molander; D Montgomery; J Moody; G F Swadling; J Weaver

doi:10.1063/1.4962043

The design of the optical Thomson scattering diagnostic for the National Ignition Facility

Rev Sci Instrum. 2016 Nov;87(11):11E549. doi: 10.1063/1.4962043.

Authors

P S Datte¹, J S Ross¹, D H Froula², K D Daub¹, J Galbraith¹, S Glenzer³, B Hatch¹, J Katz², J Kilkenny¹, O Landen¹, D Manha¹, A M Manuel¹, W Molander¹, D Montgomery⁴, J Moody¹, G F Swadling¹, J Weaver⁵

Affiliations

¹ Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
² Laboratory for Laser Energetics, University of Rochester, Rochester, New York 14623, USA.
³ SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA.
⁴ Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
⁵ Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375, USA.

PMID: 27910656
DOI: 10.1063/1.4962043

Abstract

The National Ignition Facility (NIF) is a 192 laser beam facility designed to support the Stockpile Stewardship, High Energy Density and Inertial Confinement Fusion (ICF) programs. We report on the design of an Optical Thomson Scattering (OTS) diagnostic that has the potential to transform the community's understanding of NIF hohlraum physics by providing first principle, local, time-resolved measurements of under-dense plasma conditions. The system design allows operation with different probe laser wavelengths by manual selection of the appropriate beam splitter and gratings before the shot. A deep-UV probe beam (λ₀-210 nm) will be used to optimize the scattered signal for plasma densities of 5 × 10²⁰ electrons/cm³ while a 3ω probe will be used for experiments investigating lower density plasmas of 1 × 10¹⁹ electrons/cm³. We report the phase I design of a two phase design strategy. Phase I includes the OTS telescope, spectrometer, and streak camera; these will be used to assess the background levels at NIF. Phase II will include the design and installation of a probe laser.