Gamma-ray and Radioactive Decay Spectroscopy of Heavy Proton Unbound Nuclei

重质子游离核的伽马射线和放射性衰变光谱

• 批准号: 2601516
• 金额: --
• 依托单位: University of Liverpool
• 依托单位国家: 英国
• 项目类别: Studentship
• 财政年份: 2021
• 资助国家: 英国
• 起止时间: 2021 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=studentship-2601516
• 关键词: Gamma; ray; Radioactive; Decay; Spectroscopy

Establishing the limits of observable nuclei is a long-standing challenge in nuclear physics. For proton-rich nuclei, theoretical predictions suggest that these limits are determined by two-proton emission in even-Z nuclei up to Z=82 and by the emission of a single proton for odd-Z nuclei [1-4]. Two-proton radioactivity is a rare phenomenon and experimental discoveries from ground states has been limited to a few light nuclei [5 - 10]. However, extrapolations from the table of measured masses [11] combined with advances in nuclear density functional theory have allowed candidates where two-proton radioactivity competes with a-decay in heavy nuclei to be predicted.In most cases, two-proton emission from the ground states of even-Z nuclei would occur much further from B-stability than the one-proton drip line for odd-Z nuclei due to the pairing interaction. The known cases of ground state two-proton emission in light nuclei occur around two neutrons lighter than the predicted two-proton drip line [3]. Two-proton emission from the ground states of heavy nuclei would only dominate in nuclides that lie ten or more neutrons beyond the two-proton drip line [3] and are inaccessible using current experimental facilities. However, there is a possibility that direct two-proton emission might proceed from excited states in nuclei closer to stability.This project will use decay correlation and gamma-ray spectroscopy techniques to search for rare decay modes from long-lived excited states in heavy nuclei.References[1] V.I. Goldansky, Nucl. Phys. 19 (1960) 482.[2] V.I. Goldansky, Nucl. Phys. 27 (1961) 648.[3] E. Olsen, M. Pfutzner, N. Birge, M. Brown, W. Nazarewicz, A. Perhac, Phys. Rev. Lett. 110 (2013) 222501.[4] E. Olsen, M. Pfutzner, N. Birge, M. Brown, W. Nazarewicz, A. Perhac, Phys. Rev. Lett. 111 (2013) 139903.[5] I. Mukha, et al., Phys. Rev. Lett. 99 (2007) 182501.[6] M. Pfutzner, et al., Eur. Phys. J. A 14 (2002) 279.[7] J. Giovinazzo, et al., Phys. Rev. Lett. 89 (2002) 102501.[8] M. Pomorski, et al., Phys. Rev. C 83 (2011) 061303.[9] B. Blank, et al., Phys. Rev. Lett. 94 (2005) 232501.[10] T. Goigoux, et al., Phys. Rev. Lett. 117 (2016) 162501.[11] M. Wang, G. Audi, A.H. Wapstra, F.G. Kondev, M. MacCormick, X. Xu, B. Pfeiffer, Chin. Phys. C 36 (2012) 1603.

确定可观测核的极限是核物理学中的一个长期挑战。对于富质子核，理论预测表明，这些限制是由偶数Z核（Z=82）的双质子发射和奇数Z核的单质子发射决定的[1-4]。双质子放射性是一种罕见的现象，基态的实验发现仅限于少数轻核[5 - 10]。然而，从测量质量表[11]的推断结合核密度泛函理论的进展，可以预测重核中双质子放射性与α衰变竞争的候选者。在大多数情况下，由于配对相互作用，偶Z核基态的双质子发射将比奇Z核的单质子滴线更远离B稳定性。轻核中基态双质子发射的已知情况发生在比预测的双质子滴线轻的两个中子周围[3]。来自重核基态的双质子发射仅在位于双质子滴线之外的10个或更多中子的核素中占主导地位[3]，并且使用当前的实验设施无法获得。然而，在更接近稳定的原子核中，直接的双质子发射有可能来自激发态。本项目将利用衰变关联和γ射线光谱技术，从重核的长寿命激发态中寻找稀有衰变模式。参考文献[1] V.I.第482章：你是我的女人[2]V.I. 648.第648章：你是谁？[3]E.奥尔森，M。Pfutzner，N. Birge，M.布朗，W。Nazarewicz，A. Perhac，物理学。Rev. Lett。110（2013）222501。[4]E.奥尔森，M。Pfutzner，N. Birge，M.布朗，W。Nazarewicz，A. Perhac，物理学。Rev. Lett。111（2013）139903。[5]I. Mukha等人，物理修订信函99（2007）182501。[6]M. Pfutzner等人，EUR. 279.第279章：一个女人[7]J. Giovinazzo等人，物理修订信函89（2002）102501。[8]M. Pomorski等人，Phys.Rev.C83（2011）061303。[9]B。Blank等人，物理修订信函94（2005）232501。[10]T. Goigoux等人，物理修订信函117（2016）162501. [11]M. Wang，G.奥迪，A.H. Wapstra，F.G. Kondev，M. MacCormick，X. Xu，B.普发阿成C 36（2012）1603.