93Nb(n,2n)92mNb反应截面测量

用活化法以^27Al(n,α)^24Na反应截面为中子注量标准，对14MeV能区中子引起的^93Nb(n,2n)^92mNb反应截面进行了测量。中子能量由硅探测器法测定。     

63Cu(n,α)60Co反应截面测量

本文报告了E_n=13.6—14.8MeV中子能区用活化法以²⁷Al(n,α)²⁴Na截面为中子注量标准得的⁶³Cu(n,α)⁶⁰Co的反应截面.在中子能量为13.64,13.79,14.03,14.33,14.60和14.80MeV的截面值分别为58.3±3.1,56.3±2.4,53.4±2.0,50.8±1.9,48.4±1.7和47.4±1.7mb.在文中还列举了一些作者的数据以作比较.中子能量是用铌锆截面比法测定的.     

160Gd(n,2n)159Gd和158Gd(n,p)158Eu反应截面测量

报道了在13.5—14.6MeV中子能区用活化法测得的¹⁶⁰Gd(n,2n)¹⁵⁹Gd和¹⁵⁸Gd(n,p)¹⁵⁸Eu的 反应截面值. 中子注量用⁹³Nb(n, 2n)⁹²m Nb反应截面得到. 由(13.5±0.2)MeV,(14.1±0.1)MeV和(14.6±0.2)MeV中子引起的¹⁶⁰Gd(n, 2n) ¹⁵⁹Gd反应截面值分别为(1940±83)mb, (2324±92)mb和(1983±77)mb, ¹⁵⁸Gd(n, p) ¹⁵⁸Eu反应截面值分别为(1.9±0.1)mb, (2.1±0.1)mb和(3.5±0.1)mb. 单能中子由T(d, n)⁴He反应获得.文中还列举了已收集到的数据以作比较.     

Possible Experimental Evidence of a Moderate Proton Halo in ^29S

The total reaction cross sections (TRCSs) of^29S ^28Si have been measured at intermediate energies. An obvious enhancement in TRCS of ^29S is observed as compared with its neighbouring nuclei. The TRCSs of ^29S ^28Si arecal culated with the modified Glauber theory in the optical limit and few-body approaches. The different factor d as a possible measure of halo appearance is deduced from the experimental and theoretical data. It is well accepted that ^27p is a proton halo nucleus. Although not as anomalous as ^27p, the different factor d of ^29S is obviously larger than that of its neighbouring isotones of N = 13. This result indicates that a moderate proton halo may exist in ~9S nucleus. We calculate the total reaction cross sections for ~9S with the modified Glaubertheory as a function of incident energy and compare the results with those for 2rSi which is a core nucleus 0f29S.The measured TRCSs of 27Si4-2SSi can be described to be satisfactory by the modified Glauber theory of theoptical limit approach. Although a diffused nuclear density distribution is used, the theories still inadequatelypredict the experimental TRCSs of 29S4-2SSi, which further indicates the possibility of proton halo in 29S.     

入射能量为5.1MeV中子58Ni(n,α)55Fe反应截面和出射粒子角分布测量

用屏栅电离室测量了入射中子能量为5.1MeV的⁵⁸Ni(n,α)⁵⁵Fe核反应的α粒子角分布,²³⁸U裂变电离室作中子注量率的测量,测得该能点⁵⁸Ni(n,α)⁵⁵Fe的总截面为(47.4±5.0)mb.用中国核数据中心推荐的理论计算程序UNF计算了在1—8MeV能区⁵⁸Ni(n,p)⁵⁸Co,⁵⁸Ni(n,α)⁵⁵Fe的反应截面和入射中子能量为5.1MeV的⁵⁸Ni(n,α)反应角分布.理论和测量数据的比较说明,用复合核模型来描写该能点的角分布是可行的.     

14MeV钕的同位素反应截面的测量

报道了在13.5—14.6MeV中子能区用活化法以⁹³Nb(n,2n)^92mNb反应截面为中子注量标准测得的¹⁵⁰Nd(n,2n)¹⁴⁹Nd,¹⁴⁸Nd(n,2n)¹⁴⁷Nd和¹⁴²Nd(n,2n)¹⁴¹Nd的反应截面值.由13.5±0.2,14.1±0.1和14.6±0.2MeV中子引起的¹⁵⁰Nd(n,2n)¹⁴⁹Nd反应截面值分别为2037±85,1737±68,1657±65mb,¹⁴⁸Nd(n,2n)¹⁴⁷Nd反应截面值分别为1394±58,1416±54,1956±76mb,^{142Nd(n,2n)141Nd反应截面值分别为1501±59,1623±62,1764±111mb.单能中子由T(d,n)4He反应获得.文中还收集了已发表的数据以作比较.}     

58Ni(n,p),60Ni(n,p),62Ni(n,α)和54Fe(n,p)反应截面的测量与评价

本实验用活化法测量了中子能量在13.60MeV—17.77MeV的⁵⁸Ni(n,p)^58m+gCo,⁶⁰Ni(n,p)⁶⁰Co和⁶²Ni(n,α)⁵⁹Fe三个反应道的反应截面值,并计算了反应截面测量误差的协方差矩阵.实验的测量误差在3%—7%范围内.     

用基态特征γ射线计算同质异能态反应截面的公式及其应用

根据人工放射性的生长与衰变规律, 推导出一个在特殊情况下用基态特征γ射线计算同质异能态反应截面的公式, 并据此公式用活化法以⁹³Nb(n,2n)^92mNb反应截面为中子注量标准对¹²⁸Te(n,2n)^127mTe反应截面进行了测量. 由能量为(14.1±0.2)和(14.6±0.3)MeV的中子引发的¹²⁸Te(n,2n)^127mTe反应截面值分别为(737±69)和(853±82)mb. 单能中子用T(d,n)⁴He反应获得, 其能量用铌锆截面比法测定. 为减小热中子的(n, γ)反应的影响, 在辐照过程中对样品进行了包镉处理.     

中子学实验近期进展

文章作者采用核活化法和核裂变法实验研究了加速器D-T中子、D-D中子以及~(252)Cf自发裂变中子在纯水泥体上的反射中子,获得了反射中子引起的6种高阈能活化箔的活化反应率以及~(235)U(包镉)和~(238)U裂变反应率.采用反冲质子法测量了4种厚度(4.5,9,18,27cm)聚乙烯板的角度中子谱.获得了聚乙烯铁铍组合壳体内距装置中心0,9.7,12.8和17.3cm 4个位置1MeV以上的中子能谱.采用铝核素标准截面相对测量法,获得了~(175)Lu、~(89)Y核素的(n,2n)反应截面.文章还分析了实验的不确定度.