Investigation of nuclear structure change expected for neutronrich deformed nuclei by means of lifetime measurements in sub-nanosecond region

我们研制了一台由LaBr3和薄塑料闪烁体组成的光谱仪，旨在测量能级寿命。对于能量在100keV左右的γ射线，能谱仪的时间分辨率为600ps。这意味着光谱仪有足够的能力测量精确到亚纳秒的时间范围内的寿命。观察到的质量分离^&lt；93&gt；sr和^&lt；148&gt；Ce的能级寿命与经过充分评估的先前的值一致。首次获得了98.2keV能级的寿命为8.5(5)ns。

We have developed a spectrometer consisting of a LaBr_3 and a thin plastic scintillator, aiming for use to measure level lifetimes. The spectrometer showed a good time resolution of 600ps for γ rays with energies around 100keV. This means that the spectrometer is sufficiently capable of measuring lifetimes in a time range down to sub-nanosecond. Level lifetimes observed for mass-separated ^<93>Sr and ^<148>Ce agreed with the well-evaluated previous values. The lifetime of 8.5(5)ns for the 98.2keV level in ^<148>Pr was successfully obtained for the first time.