Structure of neutron-rich nuclei around the N = 126 closed shell; the yrast structure of 205Au126 up to spin-parity $I^{pi}$ = (19/2+)
Structure of neutron-rich nuclei around the N = 126 closed shell; the yrast structure of 205Au126 up to spin-parity $I^{pi}$ = (19/2+)
复制标题
N=126闭壳层周围富中子核的结构；
DOI：
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发表时间：
2009
期刊：
影响因子：
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通讯作者：
O. Wieland
中科院分区：
文献类型：
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作者：
Z. Podolyák;S. Steer;S. Pietri;M. Gorska;P. Regan;D. Rudolph;A. Garnsworthy;R. Hoischen;J. Gerl;H. Wollersheim;H. Grawe;K. Maier;F. Becker;P. Bednarczyk;L. Caceres;P. Doornenbal;H. Geissel;J. Grebosz;A. Kelić;I. Kojouharov;N. Kurz;F. Montes;W. Prokopowicz;T. Saito;H. Schaffner;S. Tashenov;A. Heinz;T. Kurtukian;G. Benzoni;M. Pfützner;A. Jungclaus;D. Balabanski;C. Brandau;B. A. Brown;A. Bruce;W. Catford;I. Cullen;Z. Dombrádi;M. Estevez;W. Gelletly;G. Ilie;J. Jolie;G. Jones;M. Kmiecik;F. Kondev;R. Krücken;S. Lalkovski;Z. Liu;A. Maj;S. Myalski;S. Schwertel;T. Shizuma;P. Walker;E. Werner;O. Wieland
重中子富集核已通过 $ensuremath ^{208}_{ 82}{ 的相对论分裂而填充
m Pb}$ 光束在 $ensuremath E/A = 1$ GeV 上 $ensuremath 2.5 {
m g/cm^2}$ 厚 为目标。使用 GSI 的片段分离器在飞行中选择并鉴定合成的核。生产后大约 300 ns，选定的原子核被植入 $ensuremath sim 8$ 毫米厚的有机玻璃塞中，该塞子位于 RISING $ensuremath gamma$ 射线探测器光谱仪阵列的中心。在 N = 126 闭壳核 $ensuremath ^{205}_{ 79}{ 中观察到一种先前未报道的半衰期 $ensuremath T_{1/2} = 163(5)$ ns 的异构体
米金}$ .通过$gamma$射线单波和$gamma$-$gamma$符合分析建立了能级方案。与壳模型计算的比较初步确定了激发态的自旋宇称，包括异构体本身，发现其为 $ensuremath I^{pi} = (19/2^+)$ 。
Heavy neutron-rich nuclei have been populated through the relativistic fragmentation of a $ensuremath ^{208}_{ 82}{
m Pb}$ beam at $ensuremath E/A = 1$ GeV on a $ensuremath 2.5 {
m g/cm^2}$ thick Be target. The synthesised nuclei were selected and identified in-flight using the fragment separator at GSI. Approximately 300 ns after production, the selected nuclei were implanted in an $ensuremath sim 8$ mm thick perspex stopper, positioned at the centre of the RISING $ensuremath gamma$ -ray detector spectrometer array. A previously unreported isomer with a half-life $ensuremath T_{1/2} = 163(5)$ ns has been observed in the N = 126 closed-shell nucleus $ensuremath ^{205}_{ 79}{
m Au}$ . Through $ gamma$ -ray singles and $ gamma$ -$ gamma$ coincidence analysis a level scheme was established. The comparison with a shell model calculation tentatively identifies the spin-parity of the excited states, including the isomer itself, which is found to be $ensuremath I^{pi} = (19/2^+)$ .