A new isotope of Hs was produced in the reaction ${}^{208}\mathrm{Pb}({}^{56}\mathrm{Fe},n){}^{263}\mathrm{Hs}$ at the 88-Inch Cyclotron of the Lawrence Berkeley National Laboratory. Six genetically correlated nuclear decay chains have been observed and assigned to the new isotope ${}^{263}\mathrm{Hs}$. The measured cross section was ${21}_{-8.4}^{+13}$ pb at 276.4 MeV lab frame center-of-target beam energy. ${}^{263}\mathrm{Hs}$ decays with a half-life of $0.{74}_{-0.21}^{+0.48}$ ms by $\alpha$-decay and the measured $\alpha$-particle energies are 10.57 ± 0.06, 10.72 ± 0.06, and 10.89 ± 0.06 MeV. The experimental cross section is compared to a theoretical prediction based on the Fusion by Diffusion model [W. J. Świątecki et al., Phys. Rev. C 71, 014602 (2005)].

• Received 23 October 2008

DOI:https://doi.org/10.1103/PhysRevC.79.011602