论文标题
从$β^ - $^ - $^{47} $ k的$^{47} $ ca的光谱研究
Spectroscopic study of $^{47}$Ca from the $β^-$ decay of $^{47}$K
论文作者
论文摘要
$β^ - $ $ n7} $ k的$^{47} $ ca是一种适当的机制，用于基准跨越$ sd $和$ pf $ shell的相互作用，但是当前对$β^ - $ - 衰减方案的知识是有限的。我们对$β^ - $ - 衰减的$^{47} $ k进行了高分辨率，高效研究，并在Triumf-ISAC上使用了Griffin光谱仪。该研究揭示了48个新的过渡，这是$^{47} $ k半衰期（17.38（3）〜s）的更精确的价值，以及八个激发状态的新旋转和奇偶校验分配。这里首次提出的水平将$β^ - $衰减的最高状态提高到568（3）$ Q $ - 价值的KEV，并确认先前测量的大$β^ - $ - 衰减的分支比率。以前未观察到的$β^ - $ - 馈送到4.5至6.1〜MEV激发能量之间的3/2 $^+$状态，总计$β^ - $ - 喂养强度为1.29（2）\％。这些状态的$ b（gt）$值的总和表明，$ 1S_ {1/2} $质子孔在此激发能量附近的强度与先前已知的$ 1S_ {1/2} $质子和中子孔强度相当。
The $β^-$ decay of $^{47}$K to $^{47}$Ca is an appropriate mechanism for benchmarking interactions spanning the $sd$ and $pf$ shells, but current knowledge of the $β^-$-decay scheme is limited. We have performed a high-resolution, high-efficiency study of the $β^-$-decay of $^{47}$K with the GRIFFIN spectrometer at TRIUMF-ISAC. The study revealed 48 new transitions, a more precise value for the $^{47}$K half-life (17.38(3)~s), and new spin and parity assignments for eight excited states. Levels placed for the first time here raise the highest state observed in $β^-$ decay to within 568(3) keV of the $Q$-value and confirm the previously measured large $β^-$-decay branching ratios to the low-lying states. Previously unobserved $β^-$-feeding to 3/2$^+$ states between 4.5 and 6.1~MeV excitation energy was identified with a total $β^-$-feeding intensity of 1.29(2)\%. The sum of the $B(GT)$ values for these states indicates that the $1s_{1/2}$ proton hole strength near this excitation energy is comparable to the previously known $1s_{1/2}$ proton and neutron hole strengths near 2.6 MeV.
