Anomalous effects during the interaction of subatmospheric D2 (H2) with Pd from 900 ‡C to room temperature

Abstract

The interaction of subatmospheric (900 mbar) D2 or H2 with Pd sheet samples has been investigated isochorically, while the temperature was slowly decreasing from 900 to 20 °C. As predicted, maximum gas absorption has been observed below 100 °C, however the average D/Pd and H/Pd atomic ratios here achieved, 0.8–0.9, exceed literature provisions; furthermore anomalous metastable absorption (D/Pd ≅ 0.35) was tested in the range 500–200 °C. CR-39 charged-particle detectors after exposure to D-loaded sheets always revealed large number of tracks, whereas no emission was monitored from H-loaded samples: if the tracks have been due to D-D fusion fragments, the estimated average fusion rate is about 10−19 fusionper couple of deuteronsper second. Significant neutron count increase over background matching with D absorption was systematically observed, which fits with an average fusion rate ≅ 10−21 fusionper couple of deuteronsper second; such datum however is made intriguing by a similar n-excess measured during H absorption.