New isotope <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>Ds</mml:mi><mml:mprescripts/><mml:none/><mml:mn>276</mml:mn></mml:mmultiscripts></mml:math> and its decay products <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>Hs</mml:mi><mml:mprescripts/><mml:none/><mml:mn>272</mml:mn></mml:mmultiscripts></mml:math> and <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mmultiscripts><mml:mi>Sg</mml:mi><mml:mprescripts/><mml:none/><mml:mn>268</mml:mn></mml:mmultiscripts></mml:math> from the <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mmultiscripts><mml:mi>Th</mml:mi><mml:mprescripts/><mml:none/><mml:mn>232</mml:mn></mml:mmultiscripts><mml:mo>+</mml:mo><mml:mmultiscripts><mml:mi>Ca</mml:mi><mml:mprescripts/><mml:none/><mml:mn>48</mml:mn></mml:mmultiscripts></mml:mrow></mml:math> reaction

The $^{232}\mathrm{Th}+^{48}\mathrm{Ca}$ reaction has been studied at the gas-filled separator DGFRS-2 online to the cyclotron DC280 at the SHE Factory at JINR. Three new nuclides were synthesized for the first time: a spontaneously fissioning (SF) $^{268}\mathrm{Sg}$ with the half-life ${T}_{\mathrm{SF}}=13\begin{array}{c}+17\\ \ensuremath{-}4\end{array}$ s; an \ensuremath{\alpha} decaying $^{272}\mathrm{Hs}$ with ${T}_{\ensuremath{\alpha}}=0.16\begin{array}{c}+0.19\\ \ensuremath{-}0.06\end{array}$ s and ${E}_{\ensuremath{\alpha}}=9.63\ifmmode\pm\else\textpm\fi{}0.02\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$; and $^{276}\mathrm{Ds}$ with ${T}_{1/2}=0.15\begin{array}{c}+0.10\\ \ensuremath{-}0.04\end{array}$ ms, ${E}_{\ensuremath{\alpha}}=10.75\ifmmode\pm\else\textpm\fi{}0.03\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$, and an SF branch of 57%. The decay properties of these nuclei are in agreement with the systematics of experimental partial half-lives and \ensuremath{\alpha}-decay energies of heavy known nuclei, as well as spontaneous-fission half-lives. The cross sections of the $4n$-evaporation channel of $0.07\begin{array}{c}+0.17\\ \ensuremath{-}0.06\end{array}$ pb, $0.7\begin{array}{c}+1.1\\ \ensuremath{-}0.5\end{array}$ pb, and $0.11\begin{array}{c}+0.46\\ \ensuremath{-}0.09\end{array}$ pb were measured at 231, 238, and 251 MeV, respectively.

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