We present the results from an experiment dedicated to measure the lifetime of the \(2^+_2\) state, candidate for the one-phonon mixed-symmetry state, of \(^{208}\)Po. This nucleus was studied in the \(\alpha \)-transfer reaction \(^{204}\)Pb(\(^{12}\)C,\(^{8}\)Be)\(^{208}\)Po and the lifetime of the \(2^+_2\) state was determined by utilizing the Doppler-shift attenuation method. The experimental data show that the \(2^+_2\) state decays with a sizable M1 transition to the \(2^+_1\) state revealing its isovector nature.

中文翻译：

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低地四极杆等矢量激发$$ ^ {208} $$ 208 Po的实验证据

我们提供了一个实验结果，该实验致力于测量\（^ {208} \） Po的单声子混合对称状态\（2 ^ + _ 2 \）状态的寿命。这个核是在\（\ alpha \）-转移反应\（^ {204} \） Pb（\（^ {12} \） C，\（^ {8} \） Be）\（^ {208 } \） Po和多普勒频移衰减方法确定了\（2 ^ + _ 2 \）状态的寿命。实验数据表明，\（2 ^ + _ 2 \）状态随着M 1到\（2 ^ + _ 1 \）状态的较大跃迁而衰减，揭示了其等矢量的性质。