Six new nuclides near the proton-drip line in the rare-earth region

Unknown isotopes Nd-125, Pm-128, Sm-128, Gd-137(1)), Dy-139 and Tb-139 were produced using enriched targets Mo-92, Ru-96 and Cd-106, respectively, bom barded by Ar-36 ion beam with the energies of 165-180MeV from the SFC cyclo tron of HIRFL. The six new nuclides were separated and identified by a He-j et combined with a fast-tape transport system as well as "p-gamma" and "X-g amma" coincidence measurements. Their half-lives were determined to be (0.6 0 +/- 0.15)s, (1.0 +/- 0.3)s, (0.55 +/- 0.10)s, (2.2 +/- 0.2)s, (0.6 +/- 0. 2)s and (1.6 +/- 0.2)s, respectively. Energy spectra of P-delayed protons f rom Nd-125, Pm-128, Sm-129, Gd-137 and Dy-139 decay were measured. Two gamm a-rays with the energies of 109.0 keV and 119.7 keV were assigned to EC/bet a(+) decay of Tb-139.