A charge plunger device to measure the lifetimes of excited nuclear states where transitions are dominated by internal conversion
A charge plunger device to measure the lifetimes of excited nuclear states where transitions are dominated by internal conversion
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一种电荷柱塞装置，用于测量激发核态的寿命，其中跃迁由内部转换主导
DOI：
10.1016/j.nima.2020.164454
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发表时间：
2020
期刊：
影响因子：
--
通讯作者：
Barber L
中科院分区：
文献类型：
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作者：
Barber L
Jyväskylä大学使用飞行中的质量分离器Mara，在DPUNS柱塞的基础上(Taylor等人，2013年)试制了一个装药柱塞装置。利用152Sm(32 S，4n)180Pt反应在180Pt中布居激发态。利用电荷柱塞技术对21+态进行了寿命测量，该技术依赖于对反冲电荷态分布的检测，而不是对发射的γ射线的检测。这种状态是测试电荷柱塞技术的一个很好的候选者，因为它有一个已知的寿命，并通过与γ射线发射激烈竞争的转换跃迁来去核。测得21+态的寿命为480(10)ps，这与之前报道的依赖于标准γ-射线技术的寿命一致。电荷柱塞技术是测量激发态寿命的一种补充方法，激发态通过γ射线发射和内部转换来减少布居。在不可能探测到多普勒频移的γ射线的情况下，例如，在内部转换占主导地位的重核中，它很可能是唯一可行的寿命分析方法。
A charge plunger device has been commissioned based on the DPUNS plunger (Taylor et al., 2013) using the in-flight mass separator MARA at the University of Jyväskylä. The 152 Sm (32 S, 4 n) 180 Pt reaction was used to populate excited states in 180 Pt. A lifetime measurement of the 2 1+ state was performed by applying the charge plunger technique, which relies on the detection of the charge state-distribution of recoils rather than the detection of the emitted γ rays. This state was a good candidate to test the charge plunger technique as it has a known lifetime and depopulates through a converted transition that competes strongly with γ-ray emission. The lifetime of the 2 1+ state was measured to be 480 (10) ps, which is consistent with previously reported lifetimes that relied on the standard γ-ray techniques. The charge plunger technique is a complementary approach to lifetime measurements of excited states that depopulate through both γ-ray emission and internal conversion. In cases where it is not possible to detect Doppler-shifted γ rays, for example, in heavy nuclei where internal conversion dominates, it may well be the only feasible lifetime analysis approach.