New neutron-deficient lanthanum isotopes have been produced by heavy-ion bombardments of indium, and identified by means of chemical separations and genetic relationships. The proposed mass assignments and corresponding half-lives are: ${\mathrm{La}}^{124}$, 7.2±0.5 min; ${\mathrm{La}}^{128}$, 4.2±0.5 min; ${\mathrm{La}}^{127}$, 3.8±0.5 min; ${\mathrm{La}}^{126}$, 1.0±0.3 min; and ${\mathrm{La}}^{125}$, <1 min.

• Received 13 August 1962

DOI:https://doi.org/10.1103/PhysRev.129.1284