作者: Shicheng Wang , D. Snowden-Ifft , P. B. Price , K. J. Moody , E. K. Hulet
关键词: Plutonium isotopes 、 Alpha decay 、 Alpha particle 、 Spontaneous fission 、 Fission 、 Radioactive decay 、 Atomic physics 、 Physics 、 Branching fraction 、 Hadronic decay
摘要: In addition to its two known hadronic decay modes\char22{}alpha (half-life 88 yr) and spontaneous fission (5\ifmmode\times\else\texttimes\fi{}${10}^{10}$ yr)\char22{}we have found that $^{238}\mathrm{Pu}$ also decays by emission of a Mg nucleus (\ensuremath{\sim}2\ifmmode\times\else\texttimes\fi{}${10}^{18}$ Si (\ensuremath{\sim}6\ifmmode\times\else\texttimes\fi{}${10}^{17}$ yr). This extends four (the other being $^{14}\mathrm{C}$ Ne emission) the number modes fragment mass between an alpha particle resulting from fission. The branching ratios relative are lowest yet observed: \ensuremath{\sim}6\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}17}$ for 1.4\ifmmode\times\else\texttimes\fi{}${10}^{\mathrm{\ensuremath{-}}16}$ emission.