This brief review presents current experimental evidence on the existence of deformed axially symmetric but reflection asymmetric or pear shapes in nuclei. A summary of the main findings on the properties of nuclear energy levels and electric transition probabilities is given. These experimental investigations have been possible due to the development of high efficiency gamma-detector arrays and production and availability of exotic radioactive ion beams which facilitated in-beam Coulomb excitation. The nuclear structure of odd-mass pear-shaped nuclei has assumed importance as they can be vital in solving some of the fundamental problems in physics. This paper is sequel to the publication of the book by the author on Pear-shaped Nuclei (World Scientific, 2020).

中文翻译：

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梨形核

这篇简短的综述介绍了当前关于在原子核中存在变形的轴对称但反射不对称或梨形形状的实验证据。总结了关于核能级和电跃迁概率的主要发现。由于高效伽马探测器阵列的开发以及促进束内库仑激发的外来放射性离子束的生产和可用性，这些实验研究成为可能。奇数质量梨形原子核的原子核结构具有重要意义，因为它们对于解决物理学中的一些基本问题至关重要。这篇论文是作者出版这本书的续篇梨形核（世界科学，2020）。