Qualification of a high-efficiency, gated spectrometer for x-ray Thomson scattering on the National Ignition Facility

T Döppner; A L Kritcher; P Neumayer; D Kraus; B Bachmann; S Burns; R W Falcone; S H Glenzer; J Hawreliak; A House; O L Landen; S LePape; T Ma; A Pak; D Swift

doi:10.1063/1.4890253

Qualification of a high-efficiency, gated spectrometer for x-ray Thomson scattering on the National Ignition Facility

Rev Sci Instrum. 2014 Nov;85(11):11D617. doi: 10.1063/1.4890253.

Authors

T Döppner¹, A L Kritcher¹, P Neumayer², D Kraus³, B Bachmann¹, S Burns¹, R W Falcone³, S H Glenzer⁴, J Hawreliak¹, A House¹, O L Landen¹, S LePape¹, T Ma¹, A Pak¹, D Swift¹

Affiliations

¹ Lawrence Livermore National Laboratory, Livermore, California 94550, USA.
² Gesellschaft für Schwerionenphysik, 64291 Darmstadt, Germany.
³ University of California, Berkeley, California 94720, USA.
⁴ SLAC National Accelerator Laboratory, Menlo Park, California 94309, USA.

PMID: 25430193
DOI: 10.1063/1.4890253

Abstract

We have designed, built, and successfully fielded a highly efficient and gated Bragg crystal spectrometer for x-ray Thomson scattering measurements on the National Ignition Facility (NIF). It utilizes a cylindrically curved Highly Oriented Pyrolytic Graphite crystal. Its spectral range of 7.4-10 keV is optimized for scattering experiments using a Zn He-α x-ray probe at 9.0 keV or Mo K-shell line emission around 18 keV in second diffraction order. The spectrometer has been designed as a diagnostic instrument manipulator-based instrument for the NIF target chamber at the Lawrence Livermore National Laboratory, USA. Here, we report on details of the spectrometer snout, its novel debris shield configuration and an in situ spectral calibration experiment with a Brass foil target, which demonstrated a spectral resolution of E/ΔE = 220 at 9.8 keV.