Numerical experiments on the total D–D fusion neutron yield versus deuterium pressure for different energy plasma focus devices using the Lee model code

Abstract

Abstract Numerical experiments using the Lee model code were carried out to compute the total D–D fusion neutron yield versus initial deuterium pressure for nine different plasma focus devices [PF50, AACS, PF400J, PF2.2, UNU-ICTP, PFZ200, PF24, PF78, Poseidon]. The computed data were compared with the published experimental results. In addition, the maximum discharge current, the pinch current and the pinch ion number density, as a function of initial deuterium pressure, were discussed, as well as their effect on the neutron yield. The optimum pressures that correspond to the maximum neutron yield Y n were obtained for all considered devices, with reference to the specific plasma focus properties. The scaling laws for the D–D fusion neutron production, in terms of storage energies E 0 and pinch current I pinch, were derived. The scaling of Y n with I pinch and E 0 over the whole range of investigated energies up to 300 kJ has been obtained as follows: Y n ∼ I pinch 5 ,   Y n ∼ E 0 1.95 . These laws are important in the planning and design of a plasma focus as a potentially powerful pulse neutron source.