Fine structure of α decay in 222Pa

With the help of the gas-filled recoil spectrometer SHANS and a digital data acquisition system, the fine structure of the \begin{document}$\alpha$\end{document} decay for \begin{document}$^{222}$\end{document} Pa was studied. The nuclides were produced through the 1p3n evaporation channel via the heavy-ion induced fusion evaporation reaction \begin{document}$^{40}$\end{document} Ar + \begin{document}$^{186}$\end{document} W. Based on the ER- \begin{document}$\alpha 1$\end{document} - \begin{document}$\alpha 2$\end{document} - \begin{document}$\alpha 3$\end{document} and \begin{document}$\alpha$\end{document} - \begin{document}$\gamma$\end{document} correlation measurement, three new \begin{document}$\alpha$\end{document} decays were observed in addition to the three branches known previously. The one with the largest \begin{document}$\alpha$\end{document} decay energy was regarded as the ground state to ground state transition. The newly measured \begin{document}$\alpha$\end{document} decay properties of \begin{document}$^{222}$\end{document} Pa were examined in a framework of reduced width.