Phys.Lett. B 834, 137484 (2022)

M.H.Huang, Z.G.Gan, Z.Y.Zhang, L.Ma, J.G.Wang, M.M.Zhang, H.B.Yang, C.L.Yang, X.Y.Huang, Z.Zhao, S.Y.Xu, L.X.Chen, X.J.Wen, Y.F.Niu, C.X.Yuan, Y.L.Tian, Y.S.Wang, J.Y.Wang, M.L.Liu, Y.H.Qiang, W.Q.Yang, H.B.Zhang, Z.W.Lu, S.Guo, W.X.Huang, Y.He, Z.Z.Ren, S.G.Zhou, X.H.Zhou, H.S.Xu, V.K.Utyonkov, A.A.Voinov, Yu.S.Tsyganov, A.N.Polyakov

α decay of the new isotope ²⁰⁴Ac

RADIOACTIVITY ^204,205Ac(α) [from ¹⁶⁹Tm(⁴⁰Ca, xn), E=202, 210, 212, 214 MeV using SHANS2 separator at CAFE2 and SHANS separator at HRIFL, Lanzhou accelerator facility]; ²⁰⁰Fr, ¹⁹⁶At(α) [from ²⁰⁴Ac α-decay chain]; measured evaporation residues (ERs), Eα, (ER)α-α-α correlated events, production cross sections, T_1/2 of decays using two multiwire proportional counters for implanted events, double-sided silicon strip detectors (DSSSDs) for α particles, and a segmented clover Ge detector for γ radiation. ^204,205Ac, ²⁰⁰Fr, ¹⁹⁶At; deduced T_1/2 of decays of ground-state decays, and Eα values, reduced α-width in Rasmussen formalism, favored α decay for ²⁰⁴Ac decay. ²⁰⁴Ac(p); no proton decay events observed. ^{201,201m,202,202m,203,204,205}Fr, ^204,205,206Ra(α); observed α spectra, (ERs)-α-α-correlated events. Comparison with previous available experimental results. Systematics of experimental and theoretical T_1/2 and Q(α) values for ^{196,197,198,199,200,201,202,203,204,205,206,207,208,209,210,211}At, ^{198,199,200,201,202,203,204,205,206,207,208,209,210,211,212,213}Fr, ^{203,204,205,206,207,208,209,210,211,212,213,214,215}Ac, ^{211,212,213,214,215,216,217}Pa, using Hartree-Fock-BCS (HFBSC) method, and macroscopic-microscopic (MM) mass formula for theory.

doi: 10.1016/j.physletb.2022.137484