Decay properties of the neutron-deficient isotope ${}_{242}\mathrm{Es}$

The radioactive decay properties of ${}_{242}\mathrm{Es}$ were studied at the gas-filled recoil separator TASCA. This isotope was produced in the $3n$ evaporation channel of the fusion reaction of ${}_{48}\mathrm{Ca}+{}_{197}\mathrm{Au}$. A half-life of 16.9(8) s was deduced from 662 $\alpha$ decays of ${}_{242}\mathrm{Es}$, resulting in an $\alpha$-decay branching of 41(3)%. Twenty-six fission events with a half-life of $18.2_{-3.0}^{+4.5}s$ were assigned to originate from the electron-capture delayed fission of ${}_{242}\mathrm{Es}$. The probability for the electron-capture delayed fission was measured to be 0.015(4), which improves and resolves ambiguities in available experimental data. We discuss all known cases for electron-capture delayed fission in Es, Bk, and Am isotopes and compare experimental data with predictions from a recent semiempirical model. A cross section of 27(3) nb was measured for the production of ${}_{242}\mathrm{Es}$.