Nuclear structure at the proton drip line and at ultra high spin

该建议有两个部分，这两个部分都涉及极端条件下原子核结构的研究。第一部分是研究质子与中子之比改变为与稳定核中发现的质子与中子之比非常不同的核。在质子滴线处，有如此多的质子（相对于中子的数量），以至于不能再添加。这是质子中子比稳定性的极限。这项工作将研究具有变形（橄榄球）形状的这种类型的核的性质，并将结果与稳定核中发现的结果以及核模型预测的结果进行比较。工作的第二部分涉及在极高自旋的极端，就在原子核由于裂变而分裂之前，对原子核结构的研究。在这项工作中，我们将集中讨论在这个极端质量160附近的原子核中对力的作用。第一部分工作将在加拿大的TRIUMF实验室进行，2007年，该实验室将有一个新的放射性束设施和伽马射线光谱仪。这些设施对这项工作至关重要。对于第二部分的工作，我们已经获得了光束时间的实验160 Er和邻近的核使用的伽马球光谱仪在美国阿贡国家实验室。这是世界上唯一一个可以在非常高的自旋下进行这种详细的核结构工作的设施。我们预计这一试验将安排在2007年上半年进行。高自旋工作将与达雷斯伯里实验室合作，并将成为一个补充研究计划的一部分，涵盖最高自旋原子核结构的几个方面。

The proposal has two parts both of which concern the study of the structure of nuclei under extreme conditions. The first part is the study of nuclei where the proton to neutron ratio is changed to be very different from that found in stable nuclei. At the proton drip line there are so many protons (relative to the number of neutrons) that no more can be added. This is the extreme of stability in terms of the proton neutron ratio. This work will study the properties of nuclei of this type that have a deformed (rugby ball) shape and compare the results to those found in stable nuclei and those predicted by nuclear models. The second part of the work concerns the study of nuclear structure at the extreme of very high spin, just before the nucleus breaks up due to fission. In this work we will concentrate on the role of the pairing force in nuclei near mass 160 at this extreme. The first part of the work will take place at the TRIUMF laboratory in Canada where a new radioactive beam facility and gamma-ray spectrometer become available in 2007. These facilities are vital for this work. For the second part of the work we have already been awarded beam time for an experiment on 160Er and neighbouring nuclei using the GAMMASPHERE spectrometer at the Argonne National Laboratory, USA. This is the only facility worldwide available to carry out this type of detailed nuclear structure work at very high spin. We expect that this experiment will be scheduled in the first half of 2007. The high spin work will be in collaboration with Daresbury Laboratory and will form part of a complementary research programme covering several aspects of the structure of nuclei at the highest spins.