在浦项中子装置(PNF)的100 Me V电子直线加速器上利用透射法和飞行时间法测量了209Bi的0.1~100 e V的中子全截面。文中对于实验装置特点、用吸收片法拟合本底、拟合中子飞行距离和时间零点的处理过程做了较为详细的描述。测量结果与以前发表的实验数据以及评价数据ENDF/B-VII.1做了比较,比较结果符合得较好。
Measurements of neutron total cross sections of natural bismuth in the neutron energy region from 0.1 to 100 e V have been performed by using the time-of-?ight method at the Pohang Neutron Facility which consists of an electron linear accelerator, a water-cooled tantalum target with a water moderator,and a 12 m long time-of-?ight path. A6Li-Zn S(Ag) scintillator with a diameter of 12.5 cm and a thickness of 1.6 cm is employed as a neutron detector, and a piece of high purity natural bismuth metallic plates with a thickness of 3 mm is used for the neutron transmission measurement. The present results were compared with the evaluated data from ENDF/B VII.1 and other previous reported experimental data.