对40Ca9.5—10.5MeV能区内几组核能级宽度的测量

本文介绍了用γ共振吸收法测量⁴⁰Ca 9603.9keV,10321.0keV两组能级和9864.6,9868.8keV一组双重态能级的能级宽度,选用³⁹K(p,γ)反应所放出的γ射线激发相应的⁴⁰Ca吸收核能级。对于9603.9keV,10321.0keV的能级宽度,这里给出了比较精确的结果,相应的能级宽度分别为Γ=188±47eV,Γ=91±15eV。对于9864.6,9868.8keV能级,结果为Γ=100±24eV,Γ=899±214eV,由于⁴⁰Ca 9864.6,9868.8keV两能级靠得很近,因此这里用γ共振吸收法测量它们的能级宽度与以往有所不同,将同时有两组γ射线用来激发同样两个能级而发生交叉激发。我们对相应的实验处理方法作了推广。此外,用(p,γ)共振产额法测量了⁴⁰Ca 9603.9keV,10321.0keV能级宽度,得到了与γ共振吸收法一致的结果。本文还对⁴⁰Ca 9603.9keV,10321.0keV能级的(p,γ)共振强度S_pγ、同位旋T等进行了讨论。 关键词：

MEASUREMENT OF SOME LEVEL-WIDTHS IN 40Ca BETWEEN 9.5 AND 10.5 MEV

The total widths of two excited states at 9603.9 keV, 10321.0 keV and of a doublet at 9864.6, 9868.8 keV in ⁴⁰Ca have been measured with resonance γ-ray absorption. The gamma radiations from ³⁹K (p, γ) reaction at E_P=1307.2 keV, 2042.8 keV and 1595.0 keV have been selected to excite the corresponding levels in ⁴⁰Ca. The accurate results for the widths of the 9603.9 keV and 10321.0 keV states are obtained for the first time, they are 188±47eV and 91±15eV, respectively. For the 9864.6 and 9868.8 keV states, they are 100±24eV and 899±214 eV. Because the 9864.6 and 9868.8 keV states are close-lying doublet, the resonance γ-ray absorption techniqque was used in a special style: there will be two groups of gamma rays to be used to excite the same two levels, so the cross excitation occurs. We extended the corresponding exper mental analysis. In addition, (p,γ) yield measurenents have been made to extract the level widths of the 9603.9 keV, 10321.0 keV states. And the results are in agreement with the values deduced from resonance γ-ray absorption. The (p, γ) resonance strengths and isospins of the 9603.9 keV and 10321.0 keV states in ⁴⁰Ca have also been discussed.