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arXiv 0808.0264nucl-ex
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中子数N=20附近的形状共存:30 Mg中形变0^+_2态衰变E0的首次确认

Shape coexistence near the neutron number N=20: First identification of the E0 decay from the deformed 0^+_2 state in 30Mg

W. Schwerdtfeger, P. G. Thirolf, K. Wimmer, D. Habs, H. Mach, T. R. Rodriguez, V. Bildstein, J. L. Egido, L. M. Fraile, R. Gernhaeuser, R. Hertenberger, K. Heyd… 展开作者

W. Schwerdtfeger, P. G. Thirolf, K. Wimmer, D. Habs, H. Mach, T. R. Rodriguez, V. Bildstein, J. L. Egido, L. M. Fraile, R. Gernhaeuser, R. Hertenberger, K. Heyde, P. Hoff, H. Huebel, U. Koester, T. Kroell, R. Kruecken, R. Lutter, T. Morgan, P. Ring

摘要:

通过测量~(30)Mg的E0跃迁到基态,确定了~(30)Mg的1789 keV能级为第一激发态。测得的小值rho^2(E0,0 ^+_2 -> 0^+_1)= 5.7(14)x 10^-3意味着在N=20附近,竞争组态的混合非常小,它们的本征四极形变有很大的不同。轴对称超平均场组态混合计算确定30 Mg的基态是基于N=20壳层闭合以下的中子组态,而激发态0^+主要由两个被激发到nu 1 f_{7/2}轨道的中子组成。使用二能级模型,可以导出0.08(4)的混合振幅。

英文摘要:

The 1789 keV level in 30Mg was identified as the first excited 0^+ state by measuring its E0 transition to the ground state. The measured small value of rho^2(E0,0^+_2 --> 0^+_1) = 5.7(14) x 10^-3 implies a very small mixing of competing configurations with largely different intrinsic quadrupole deformation near N=20. Axially symmetric Beyond-Mean-Field configuration mixing calculations identify the ground state of 30Mg to be based on neutron configurations below the N=20 shell closure, while the excited 0^+ state mainly consists of a two neutrons excitated into the nu1 f_{7/2} orbital. Using a two-level model, a mixing amplitude of 0.08(4) can be derived.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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