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.

建立可观察到的核的极限是核物理学的长期挑战。对于富含质子的核，理论预测表明，这些限制是由偶数-Z核中的两种质子发射确定的，直至z = 82，以及奇数-Z核的单个质子的发射[1-4]。两种质子的放射性是一种罕见的现象，地面状态的实验发现仅限于几个光核[5-10]。然而，从测得的质量表的外推[11]与核密度功能理论的进步相结合，使候选者可以预测两个普罗替型放射性与A-Decay竞争的候选者。在大多数情况下。由于配对相互作用，偶数核的基态将比B稳定性更远的B稳定性更远。在光核中，基态两种蛋白发射的已知病例比预测的两螺旋子滴水线更轻两个中子[3]。来自重核的基态的两种蛋白发射仅在两个或多个中子以外的中子以外的核素中占主导地位[3]，并且使用当前的实验设施无法访问。但是，有可能是直接两种蛋白的发射可能是从更接近稳定性的核中激发状态进行的。该项目将使用衰减相关性和伽马射线光谱技术来寻找来自重型核中长核状态的稀有衰减模式引用[1] v.i. Goldansky，Nucl。物理。 19（1960）482。[2] V.I. Goldansky，Nucl。物理。 27（1961）648。[3] E. Olsen，M。Pfutzner，N。Birge，M。Brown，W。Nazarewicz，A。Perhac，Phys。莱特牧师。 110（2013）222501。[4] E. Olsen，M。Pfutzner，N。Birge，M。Brown，W。Nazarewicz，A。Perhac，Phys。莱特牧师。 111（2013）139903。[5] I. Mukha等人，物理学。莱特牧师。 99（2007）182501。[6] M. Pfutzner等，Eur。物理。 J. A 14（2002）279。[7] J. Giovinazzo等人，物理学。莱特牧师。 89（2002）102501。[8] M. Pomorski等人，物理学。 Rev. C 83（2011）061303。[9] B. Blank等人，物理学。莱特牧师。 94（2005）232501。[10] T. Goigoux等人，物理。莱特牧师。 117（2016）162501。[11] M. Wang，G。Audi，A.H。Wapstra，F.G。 Kondev，M。MacCormick，X。Xu，B。Pfeiffer，Chin。物理。 C 36（2012）1603。