The fusion gamma has an advantage to measure fusion reaction history in the deuterium-tritium (DT) fuel implosion experiments. A gas Cherenkov detector is available to measure DT fusion gamma in a high background environment. Simulation is carried out by Geant4 to evaluate the conversion efficiency and the time response of this Cherenkov detector. The background gamma rays are roughly estimated based on ENDF/B-VII.0 data, and the signal-to-noise (SNR) is evaluated based on the simulated energy response curve. The simulation result and the SNR analysis are helpful to construct the Cherenkov detector at Shenguang-III facility.
Areal density (ρR) is one of the crucial parameters in the inertial confinement fusion. Measurement of the fusion products is a more feasible method to diagnose ρR than other methods, such as X-ray. In the capsules filled with D<sub>2</sub> fuel or D-<sup>3</sup>He fuel, proton is an ideal probe to diagnose the implosion ρR in different emission times and directions by measurements of the proton yields and spectra. By D-D reaction protons and D-<sup>3</sup>He reaction protons, the diagnostics of the total and fuel ρR, ρR evolution, implosion asymmetry and mix effect have been demonstrated at OMEGA and NIF facilities. Also some advanced proton diagnostics instruments are developed with a high level capability. Preliminary diagnosis of ρR in the deuterium involved fuel capsules by measurement of protons at SG-III facility was implemented. A fusion product emission and transport code by Monte-Carlo method was developed. The primary and secondary protons emission and transport in the fuel and shell plasmas were able to be simulated. The relations of the proton energy loss and the secondary proton yields with the areal density were inspected. Several proton spectrometers have been built up at SG-III facility, such as a step ranged filter (SRF) proton spectrometer and a wedged range filter (WRF) proton spectrometer. Some proton response simulation codes and the codes for proton spectra reconstruction were also developed. The demonstrations of ρR diagnostics at SG-III facility by D-D reaction and D-<sup>3</sup>He reaction proton spectra measurements are presented.