Fusion reactions during low energy deuterium implantation into titanium

Abstract

In the search for ‘cold fusion’ reactions in solids loaded with deuterium atoms at high concentration, ion implantation has been used as a means to reach the required high deuterium concentration in the lattice. In the present investigations, 300 eV to 6 keV D+ ions were injected into 3 μm thick titanium foils at room temperature and at 140 K. The protons from the D(d,p)T reaction were monitored using a solid state detector with a large solid angle, both during and after implantation. After implantation of deuterium in the titanium foil up to saturation, i.e. with about 1.8 deuterium atoms per titanium atom at room temperature, the possible fusion reaction rate at equilibrium was determined over a period of 65 h. The measured count rate was within the limits of the natural background, and an upper limit of 1 × 10−23 per deuterium pair per second was established. During implantation of deuterium at energies between 3 and 6 keV, the count rate is dominated by reactions of the incident energetic deuterons with deuterons already implanted in the foil. The D-D reaction cross-sections, evaluated at 140 K, follow closely those obtained by extrapolation of the Gamow function to low energies. During implantation of 300 eV D+ ions, no counts from the D(d,p)T reactions were monitored, showing that even under extreme conditions of non-equilibrium the possible ‘cold fusion’ reaction rate is smaller than the background count rate.

Fusion physics and philosophy

“…Figure 4 is a quantitative presentation of the cross section for two deuterons reacting to yield a proton and triton as a function of their impact energy. 5 At one keV, the reaction probability is over one billion times lower than the peak value. Room temperature imparts thermal energies to atoms on the order of only 1/40 of one electron volt.…”

“…, as a function of the incident energy, given in kilo-electron-volts. 5 Another way to view the problem is to consider means to concentrate energy within the lattice. This involves two considerations.…”

Accelerator Experiments and Theoretical Models for the Electron Screening Effect in Metallic Environments

“…So one of the first accelerator experiments was done on Ti [21]. The authors made no effort to determine the deuteron density but used a literature value and obtained no enhancement.…”