Radiochemical Study of Nuclear Spallation and Fission at Intermediate Energies

利用日本现有加速器中的光子、中子、质子和重离子，在低能到高能下对核反应的各个方面，如层裂、裂变和碎裂等进行了放化研究，并讨论了反应机理和可能的应用。Sakamoto、Fujiwara和Shibata在60-1000 MeV对从^&lt；27&gt；Al到^&lt；201&gt；Bi的22个靶的光子化、光裂变和光碎裂进行了广泛的研究。包括铜散裂和金裂变的反冲测量。Masumoto和Ohtsuki测量了东北大学电子直线加速器250厘米混凝土屏蔽层中层裂产物的深度和角度分布。Sakamoto小组和Mitsugashira使用了这种加速器，他们报道了在高通量反应堆JMTR中研究^&lt；237&gt；Np的光裂变和^&lt；242&gt；Cm和^&lt；238；Pu的产生。Sekine进行了循环射程测量，其中发展了一种新的薄箔方法。他al…更多的研究是通过(n，g)和(g，n)反应反冲合成标记化合物。Shinohara广泛地研究了重离子引起的高达GeV能的层裂，他还在KEK PS.继续了一项重要的pi-mesic原子化学研究。核过程中的膜转移是一个非常重要的信息，并研究了Shinohara的重离子诱导反应以及工藤的质子诱导的^&lt；238&gt；U和^&lt；232&gt；Th的裂变。在许多应用中，中子和质子诱导的反应产生几十MeV的轻核如^&lt；7，10&gt；Be是至关重要的，Imamura和Shibata报道了激发函数的几个结果。Kobayashi、Nagai和Imamura已经建立了一种对长寿命放射性核素进行极其灵敏的测量，并成功地应用于上述一些反应研究。通过交换在本项目过程中获得的信息，进行了联合讨论，并探讨了我们在这一领域进一步发展的前景。较少

Radiochemical studies of various aspects of nuclear reactions such as spallation, fission and fragmentation have been performed at low to high energies by using photons, neutrons, protons, and heavy ions from available accelerators in Japan, and discussed together for reaction mechanism and their possible applications.Photopion reactions photospallation, photofission and photofragmentation of 22 targets ranging from ^<27>Al to ^<201>Bi at 60-1000 MeV were extensively studied by Sakamoto, Fujiwara and Shibata. Recoil measurements of Cu-spallation and Au-fission were included. Masumoto and Ohtsuki measured the depth and angular profiles of spallation products in a 250 cm concrete shields for Tohoku Univ.e-linac. This accelerator was used by Sakamoto group and Mitsugashira who reported studies of photofission of ^<237>Np and production of ^<242>Cm and ^<238>Pu in a high-flux reactor JMTR.Recoil range measurement was performed by Sekine, in which a new thin foil method was developed. He al … More so studied recoil synthesis of labelled compounds by (n, g) and (g, n) reactions. Heavy ion-induced spallation upto GeV energies was extensivly studied by Shinohara who also continued an important study of pi-mesic atom chemistry at KEK PS.Momentum transfer in nuclear processes is a very important information, and investigated in heavy-ion-induced reactions by Shinohara and also in proton-induced fission of^<238>U and ^<232>Th by Kudo. Neutron- and Proton- induced reactions producing light nuclei like ^<7,10>Be at several tens of MeV are of vital importance in many applications, and several results of excitation functions were reported by Imamura and Shibata. An extremely sensitive measurement of long-lived radionuclides has been established by Kobayashi, Nagai and Imamura, and successfully applied to some of the above-mentioned reaction studies. Combined discussions were performed by exchanging information obtained during the course of the present project, and our prospects for further developments in this field have been exploited. Less