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We have carried out a series of experiments to test the recently claimed observations of cold fusion. In a first experiment, we used an electrochemical cell with a Pd wire cathode. Neutrons were detected by the1H(n,?) photons from surrounding water and paraffin. In a second experiment, two vacuum-cast Pd disks were the cathodes in “twin” cells, one with H2O, and the other with D2O. The two cells were shuttled every 24 hours between similar detector setups, equipped with neutron, ?- and x-ray detectors. A third experiment was designed to measure production of charged particles, using an Si surface barrier detector viewing the back of a 76-µm thick Pd foil cathode. No statistically-significant evidence of nuclear fusion has been obtained in any of these experiments, either in steady-state operation or in transient response to a variety of perturbations. Upper bounds on the rate of various postulated fusion processes were set including <2×10-23 neutrons (dd pair)-1 s-1 for the d(d,n)3He reaction and <6×10-25 protons (dd pair)-1 s-1 for the d(d,p)3H reaction (2s level). Chemical analysis of our electrolytes revealed no anomalous increase in3H concentrations. (PACS numbers: 82.45.+z,29.30.-h,29.70.-e,25.45.-z).

Beta-delayed neutrons and high-energy?-rays following decay of137I have been studied in order to characterizeß-decay to and deexcitation of neutron-unbound levels in137Xe. The total?-ray intensity observed accounts for at least 20% of theß-intensity to levels aboveBn. No evidence was found for neutron and?-ray emission from the same levels. With the experimentalß-strength function aboveBn detailed tests were performed on the reproduction of the experimental neutron spectrum, the level density and Porter-Thomas fluctuations of the reducedß-transition probabilities to highly excited states in137Xe.

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The level structure of88Kr has been investigated by measurements on chemically separated bromine samples. A total of 146?-rays have been assigned to the decay of88Br, and a level scheme with 58 levels is proposed. The collectivity of88Kr has been investigated within the framework of the Interacting Boson Approximation (IBA-2 model). Comparison of our detailed?-ray data and calculations have led to the establishment of a protonhole boson desciption rather than protonparticle nature. This supports recent works establishingZ=40 as a major subshell closure.

Theß-decay of 377 ms95Rb and 168ms97Rb has been thoroughly investigated by means of?-ray, conversion electron andß-delayed neutron spectroscopy. More than 97% of theß-decay to particle-bound states has been placed in level schemes of95Sr and97Sr. High-resolution neutron spectroscopic studies have allowed to extend the knowledge of the excitation spectra up to 9 MeV, respectively 10 MeV. The density of neutron-unbound levels in95Sr and97Sr has been derived from peak stripping analyses of the neutron spectra. Beta-strength functions (Sß(E)) have been investigated in detail. They indicate that Gamow-Tellerß-decay of both precursors is dominated by nuclear structure. The discovered pronounced resonances and the variation in the shape ofSß(E) are compared with predictions from the gross theory ofß-decay and shell model calculations in the random phase approximation (RPA).

A classification scheme for the different forms of implant-related damage which arise upon annealing consisting of five categories is presented. Category I damage is 'subthreshold' damage or that which results prior to the formation of an amorphous layer. If the dose is increased sufficiently to result in the formation of an amorphous layer then the defects which form beyond the amorphous/crystalline (a/c) interface are classified as category II ('end of range') damage. Category III defects are associated with the solid phase epitaxial growth of the amorphous layer. The most common forms of this damage are microtwins, hairpin dislocations and segregation related defects. It is possible to produce a buried amorphous layer upon implantation, If this occurs, then the defects which form when the two a/c interfaces meet are termed category IV ('clamshell', 'zipper') defects. Finally, category V defects arise from exceeding the solid solubility of the implanted species in the substrate at the annealing temperature. These defects are most often precipitates or dislocation loops. In addition to presenting examples of this classification scheme, new results emphasizing category II, IV, and V defects will be presented. For category II defects, the source, dose and mass dependence as well as the influence of pre- and post-amorphization is discussed. The category IV defects which arise from buried amorphous layers in {100} oriented As implanted samples is presented. Half loop dislocations which arise during annealing of high dose As implants, are shown to originate in the category V defects and grow upon dissolution of As clusters and precipitates. [ABSTRACT FROM AUTHOR]