Alpha decay helium produced on Earth is the result of the alpha decay of underground deposits of minerals containing uranium or thorium. The helium is brought to the surface as a by-product of natural gas production. Alpha particles were first described in the investigations of radioactivity by Ernest Rutherford in 1899, and by 1907 they were identified as He ions. By 1928, George Gamow had solved the theory of alpha decay via tunneling. The alpha particle is trapped in a potential well by the nucleus. Classically, it is forbidden to escape, but according to the (then) newly discovered principles of quantum mechanics,
Dubnium by bombarding californium-249 with nitrogen-15 ions, with an alpha activity of 9.1 MeV. To ensure this activity was not from a different reaction, the team attempted other reactions: bombarding Cf with N, Pb with N, and Hg with N. They stated no such activity was found in those reactions. The characteristics of the daughter nuclei matched those of 103, implying that the parent nuclei were of 105. These results did not confirm the JINR findings regarding the 9.4 MeV or 9.7 MeV alpha decay of 105, leaving only 105 as a possibly produced isotope. JINR then attempted another experiment to