Totalβ-decay energies and masses of strongly neutron-rich indium isotopes ranging fromIn120toIn129

Abstract

Experimental total $\beta$-decay energies of strongly neutron-rich indium isotopes are presented. The samples were produced as mass-separated fission products by using the on-line isotope separator technique. By means of a Si(Li)-detector system, $\beta$ spectra were recorded in coincidence with different $\gamma$ gates, and $Q_{\beta }$ values for isomers of ${}_{}{}^{120-129}{}_{}{}^{}\mathrm{In}$ were deduced. The atomic mass excess is derived for these nuclei, and comparisons are made with mass formula predictions. The mean uncertainty of the experimental mass excesses is 0.11 MeV. The precision of the mass formulas chosen for the comparison varies widely with rms deviations ranging from 0.21 to 1.36 MeV. For the isotopes ${}_{}{}^{124-129}{}_{}{}^{}\mathrm{In}$ the possibility of delayed-neutron emission is discussed.