Radioactive decay by the emission of heavy nuclear fragments

Abstract

Radioactive decay of nuclei by the emission of heavy ions of C, N, O, F, Ne, Na, Mg, Al, Si, and P isotopes (known as exotic decay or cluster radioactivity) is reinvestigated within the framework of a semiempirical, one-parameter model based on a quantum mechanical, tunnelling mechanism through a potential barrier, where both centrifugal and overlapping effects are considered to half-life evaluations. This treatment appeared to be very adequate at fitting all measured half-life values for the cluster emission cases observed to date. Predictions for new heavy-ion decay cases susceptible of being detected are also reported.

Role of 208Pb daughter nucleus and nuclear shell effects in trans‐lead cluster radioactivity by emission of neon clusters from 218–236U isotopes

“…So far, the emission of 22 Ne, 24 Ne, 25 Ne, 26 Ne, 28 Mg, 29 Mg and 30 Mg clusters from 230,232−236 U isotopes have been experimentally confirmed [8].…”

“…Santhosh et al [26][27][28] have calculated half-lives for experimentally observed cluster decay modes of several heavy nuclei in the trans-lead region by using Coulomb Proximity potential model [CPPM]. Tavares et al [29] have investigated exotic decay of heavy nuclei within the framework of a semi-empirical, one-parameter model based on a quantum mechanical, tunneling mechanism through a potential barrier by taking into account both centrifugal and overlapping effects in half-life evaluations. Warda and Robledo [30] have recently studied CR of actinide nuclei by using mean-field Hartree-Fock-Bogoliubov theory with the phenomenological Gogny interaction.…”

O papel das emulsões nucleares na institucionalização da pesquisa em física experimental no Brasil

“…Para mais detalhes sobre a descoberta do CBPF e para posteriores comprovações experimentais e avanços teóricos, ver, por exemplo, Tavares e cols. [48].…”

“…Como dissemos, as descobertas de Lattes foram capitaneadas por um grupo de cientistas -apoiado por intelectuais, artistas, empresários, jornalistas e militares nacionalistas -cujo objetivo principal era impulsionar a criação de um centro nacional de pesquisa básica em física. 48 Ainda no plano internacional,é preciso lembrar que a energia nuclear passou a ser vista, depois da Segunda Guerra, como instrumento de poder e autonomia política pelos governos.…”

“…Vale ressaltar que as equipes de microscopistas de Powell tiveram seu fim ainda em 1957. 48 Esse centro (CBPF), no entanto, acabou sendo montado fora da universidade, em função da estrutura arcaica desta, baseada em departamentos estanques. Para ampla descrição desse cenário, ver, por exemplo, Andrade [36].…”