Neutron Yield of Thermo Scientific P385 D-T Neutron Generator vs. Current and Voltage

TL;DR

This study measures neutron yield dependence on current and voltage in the Thermo Scientific P385 D-T neutron generator, combining experimental data with theoretical modeling to understand its performance characteristics.

Contribution

It provides a comprehensive analysis of neutron yield dependence on current and voltage, integrating experimental measurements with TRIM and MCNP simulations for the P385 generator.

Findings

Neutron yield depends linearly on beam current.

Neutron yield follows a ~3.5 power law with voltage.

Maximum neutron yields are approximately 8.2×10^8 n/s and 4.5×10^8 n/s for two different tubes.

Abstract

The Thermo Scientific P385 Neutron Generator is a compact neutron source, producing 14 MeV neutrons through the deuterium-tritium (DT) fusion reaction. For practical use, it is important to measure and preferably understand the dependence of the neutron production rate on the accelerator current and voltage. In this study, we evaluated neutron production with a neutron spectrometer (BTI N-Probe), a He-3 detector surrounded by HDPE shells (Nested Neutron Spectrometer, NNS), and two ZnS fast neutron scintillators (EJ-410) for both P385 A3082 and A3083 sealed tubes. We also predicted the neutron yield using the TRIM code, which calculates the trajectory and the energy loss of deuterons and tritons within the target. Experimental and theoretical results showed a linear dependence on beam current and a $\sim$3.5 power law dependence on the operating voltage. A series of NNS measurements, neutron spectrum from N-Probe and MCNP calculation showed that the A3083 and A3082 tubes provide a maximum neutron yield of $\sim 8.2 \times 10^8$ n/s and $\sim 4.5 \times 10^8$ n/s, respectively. We showed that tritium decay was not a significant contributor to this difference.