Identification of $^{109}$Xe and $^{105}$Te

The existence of a region of alpha emitting nuclei above $^{100}$Sn is due to the presence of the Z=50 shell closures. The region is a fertile area to investigate possible enhanced correlations between neutrons and protons filling the same single-particle orbits and could lead to the observation of superallowed alpha decay as an approach is made towards $^{100}$Sn. The new isotope $^{109}$Xe was produced at the HRIBF at Oak Ridge National Laboratory. The lightest mass $\alpha$-radioactivity identified to date, $^{105}$Te, was detected through the $^{109}$Xe$\rightarrow ^{105}$Te $\rightarrow ^{101}$Sn alpha decay chain. This marks the closest approach to the N = Z line above $^{100}$Sn. The half-life and Q$_{\alpha}$ value for $^{105}$Te were used to determine the reduced $\alpha$-decay width, $\delta^{2}$. The ratio $\delta^{2}_{^{105}Te}$/$\delta^{2}_{^{213}Po}$ of 2.7 indicates a superallowed character of the $\alpha$-emission from $^{105}$Te. Fine structure in the millisecond alpha decay of $^{109}$Xe to $^{105}$Te was identified and the energy difference between the $\nu$d$_{5/2}$ ground state and the $\nu$g$_{7/2}$ first excited state was determined to be around 150 keV in $^{105}$Te. Prospects for reaching the superallowed alpha decay chain $^{108}$Xe$\rightarrow ^{104}$Te $\rightarrow ^{100}$Sn will also be discussed.