New isotope Hs263

A new isotope of Hs was produced in the reaction Pb-208(Fe-56, n)(263)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)Hs. The measured cross section was 21(-8.4)(+13) pb at 276.4 MeV lab frame center-of-target beam energy. (263)Hs decays with a half-life of 0.74(-0.21)(+0.48) ms by alpha-decay and the measured a- 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. Swiatecki et al., Phys. Rev. C 71, 014602 (2005)].