December 2018 DOE Report

A New Neutron Time-of-Flight Line of Sight on OMEGA

A set of experiments has recently been performed on OMEGA to generate a short impulse of x rays that allowed for the semi-annual calibration of the neutron temporal diagnostic (NTD), as well as the first measurements of the instrument response function (IRF) on a new 22-m neutron time-of-flight (nTOF) diagnostic. The NTD calibration is required to keep the uncertainties of the neutron production rate in cryogenic implosions below 50 ps. In addition, calibrating the newly built nTOF diagnostic line of sight (LOS) with x rays from the short impulse completes the calibration of the third nTOF detector that can measure hot-spot motion and the second nTOF detector that can measure fuel areal density.

The newly built nTOF detectors consist of a small plastic scintillator (petal detector) placed in front of a larger liquid scintillator (xylene detector), shown here.