Collective acceleration of deuterons from the residual chamber atmosphere in a Luce diode

Abstract

The collective acceleration of deuterons from the residual atmosphere of the Luce diode chamber is studied at a pressure of gaseous deuterium in the range of 0.029–0.177 Pa. The energy and number of accelerated deuterons were determined by neutron time-of-flight spectrometry and by measuring the activity of 13N and 11C radionuclides induced in B4C targets by the reactions 12C(d,n)13N and 10B(d,n)11C, the activity of the 7Be induced by the 10B(p,αγ)7Be reaction was used to control the number of accelerated protons. The neutron time-of-flight shows that the gaseous products of polyethylene anode erosion have no noticeable effect on the energy and number of deuterons accelerated in shots following the first shot of the series. It is shown that the energy of deuterons accelerated from the residual atmosphere is the same as during their acceleration from the near-anode plasma using a deuterated polyethylene anode, but the number of accelerated deuterons per shot depends on the deuterium pressure exponentially, still it is by an order of magnitude smaller even at a pressure of 0.177 Pa. The exponential growth is due to the fact that the number of accelerated deuterons strongly depends on the diode current, which increases noticeably with increasing the deuterium pressure.