β-delayed proton decays near the proton drip line

In order to improve the measuring efficiency, a “proton-gamma” coincidence technique in combination with a He-jet tape transport system was proposed and employed to identify the β-delayed proton precursors. The study of β-delayed proton decays near the proton drip line by using the “proton-gamma” coincidence technique over the last 5 years at the Institute of Modern Physics, Lanzhou, China, was summarized. New β-delayed proton precursors $121Ce,$ $125Nd,$ $128Pm,$ $129Sm,$ $135Gd,$ $137Gd,$ $139Dy,$ $142Ho,$ and $149Yb$ in the rare-earth region along a speculated proton drip line were synthesized and identified for the first time. The β-delayed proton decays of $81Zr,$ $85Mo,$ $89Ru,$ and $93Pd$ in $Tz=1/2$ series as well as $92Rh$ in $Tz=1$ series were observed.