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A study of the 7 Li( 9 Be, 4 He 9 Be) 3 H reaction at E beam =70 MeV has been performed using resonant particle spectroscopy techniques and provides a measurement of α -decaying states in 13 C. Excited states are observed at 12.0, 13.4, 14.1, 14.6, 15.2, 16.8, 17.9, 18.7, 21.3 and 23.9 MeV. This study provides the first measurement of the three highest energy states. Angular distribution measurements have been performed and have been employed to indicate the transferred angular momentum for the populated states. These data are compared with recent speculations of the presence of chain-like structures in 13 C.

In this paper an evaluation of a number of different insulating materials, under pulse breakdown conditions, is described. The experimental setup used an 8 stage Marx generator in order to generate a high potential difference (in the range 80–220 kV) between two spherical electrodes which were spaced 1.5–3.5 mm apart. The breakdown voltage of each of the materials was recorded and the data was then post-processed in order to determine the breakdown strength of each of the samples.

In order to improve the high voltage performance of pulsed power equipment a study has been undertaken into the dielectric strength of various liquids, gels and solids. The experimental set-up for this investigation used an 8 stage Marx generator in order to produce a high potential difference between two uncoated stainless steel spherical electrodes. The electrodes were insulated by the material under test and were spaced 1.5 to 3.5 mm apart. The breakdown voltage of each of the samples was recorded as a function of the gap distance, and the data was then post-processed in order to determine the breakdown strength of each of the materials. A number of substances were identified that had very high breakdown strengths and these are now being incorporated into our pulsed power devices. In addition to these tests, investigations were also undertaken on oil insulated electrodes coated with a variety of dielectric materials. A number of coatings were identified which were capable of increasing the breakdown voltage by up to 60% over uncoated electrodes. Additional results were taken for a selection of coating materials in order to evaluate the effect of coating thickness and storage temperature on the breakdown voltage performance.

The kinematically complete measurements of the 7Li(9Be,ααt)5He reaction at Ebeam = 55 and 70 MeV have been performed and the reconstructed 11B excitation energy spectra were compared with the 7Li(9Be,α7Li)5He results obtained at the same beam energies. Evidence was found for the t+8Be(g.s.) decay of the 11B excited states at 13.1 and 14.4 MeV, the α+7Li*(4.652 MeV) decay of the states at 14.4 and 17.5 MeV and for the t+8Be*(3.03 MeV) decay of the 17.5 MeV state in 11B. A study of the relative yields for the decay of the 14.4 MeV state indicates that significant part of α‐decay strength goes into the 2α+t three‐body decay channel.

Studies of the 16O(9Be,alpha 7Be)14C, 7Li(9Be,alpha 7Li)5He and 7Li(9Be,alpha alpha t)5He reactions at E(beam)=70 and 55 MeV have been performed using resonant particle spectroscopy techniques. The 11C excited states decaying into alpha+7Be(gs) are observed between 8.5 and 13.5 MeV. The alpha+7Li(gs), alpha+7Li*(4.652 MeV) and t+8Be(gs) decays of 11B excited states between 9 and 19 MeV are observed. The decay processes are used to indicate the possible three-centre 2alpha+3He (2alpha+3H) cluster structure of observed states. This cluster structure is more prominent in the positive-parity states, where two rotational bands with large deformations are suggested. Excitations of some of the observed T=1/2 resonances coincide with the energies of previously measured T=3/2 isobaric analogs of the 11Be states,indicating that these states may have mixed isospin., Comment: Contribution for the proceedings of the NUSTAR'05: NUclear STructure, Astrophysics and Reactions, University of Surrey, Guildford, UK; accepted for publication in Journal of Physics G

The first exclusive breakup measurements for the nucleus Be-9 are presented. Breakup via several discrete states is observed following scattering off C-12 and Pb-208. The results support the prediction of a recent microscopic cluster calculation for a strong n+Be-8(2(+)) state component in the second excited state.

Studies of the 16O(9Be,alpha7Be)14C and 7Li(9Be,alpha7Li)5He reactions at E{beam}=70 MeV have been performed using resonant particle spectroscopy techniques. The 11C excited states decaying into alpha+7Be(gs) are observed at 8.65, 9.85, 10.7 and 12.1 MeV as well as possible states at 12.6 and 13.4 MeV. This result is the first observation of alpha-decay for excited states above 9 MeV. The alpha+7Li(gs) decay of 11B excited states at 9.2, 10.3, 10.55, 11.2, (11.4), 11.8, 12.5,(13.0), 13.1, (14.0), 14.35, (17.4) and (18.6) MeV is observed. The decay processes are used to indicate the possible three-centre 2alpha+3He(3H) cluster structure of observed states. Two rotational bands corresponding to very deformed structures are suggested for the positive-parity states. Excitations of some observed T=1/2 resonances coincide with the energies of T=3/2 states which are the isobaric analogs of the lowest 11Be states. Some of these states may have mixed isospin., Comment: accepted for publication in Nuclear Physics A

A study of the ${}^{7}\mathrm{Li}{(}^{9}\mathrm{Be}{,}^{4}{\mathrm{He}}^{10}\mathrm{Be}{)}^{2}\mathrm{H}$ reaction at ${E}_{\mathrm{beam}}=70\mathrm{MeV}$ has been performed using resonant particle spectroscopy techniques and provides the first measurements of \ensuremath{\alpha}-decaying states in ${}^{14}\mathrm{C}.$ Excited states are observed at 14.7, 15.5, 16.4, 18.5, 19.8, 20.6, 21.4, 22.4, and 24.0 MeV. The experimental technique was able to resolve decays to the various particle bound states in ${}^{10}\mathrm{Be}$ and provides evidence for the preferential decay of the high energy excited states into states in ${}^{10}\mathrm{Be}$ at \ensuremath{\sim}6 MeV. The decay processes are used to indicate the possible cluster structure of the ${}^{14}\mathrm{C}$ excited states.

In order to search for a proposed α:2n:α:2n:α molecular structure in 16C its break-up into 10Be + 6He, 12Be + α, 8He + 2α and 6He + 6He + α has been studied using a 560 MeV 16C beam inelastically excited on a 12C target. States in 16C appear to be only weakly populated in this reaction.