�ber die Wechselwirkung zwischen Neutronen und Atomkernen

Enrico Fermi’s Discovery of Neutron-Induced Artificial Radioactivity: Neutrons and Neutron Sources

“…47 They interpreted their surprising observation by assuming that a new radioactive isotope of phosphorous was created, which then decayed exponentially through the emissions of positrons, according to the two reactions: 13 Al 27 + 2 He 4 → 15 P 30 + 0 n 1 15 P 30 → 14 Si 30 + 1 e + .…”

“…"* In the former case of aluminum, after being irradiated for two hours, he observed "a considerable increase in the rate of pulses," and then an exponential decrease with a half-life of about 12 minutes. He interrelated this case similarly, according to the reaction 13 Al 27 + 0 n 1 → 11 Na 24 + 2 He 4 , where the "atom Na 24 must be a new radioactive isotope, which, through the emission of a β-particle, transforms into [ 12 Mg 24 ]." 62 "If these interpretations are correct," Fermi concluded, "we have here an artificial formation of radioactive elements emitting ordinary β-particles, in contradistinction to the substance discovered by Joliot, which emit positrons."…”

Нейтрон

“…Если бы можно было доказать, что эта точка зрения правильна, мы имели бы первый случай превращения элементов, при котором бомбарди-рующая частица остается незахваченной. Разрушение нейтронами азота было обнаружено также Мейтнер и Филиппом 13 ' , Гаркинсом, Гансом и Ньюсоном и Кюри . Фэзер 16 также наблюдал раздвоенные Следы, появляющиеся в кислороде.…”