Fine structure in the alpha decay of U-224

Lopez-Martens, A; Hauschild, K; Rezynkina, Kseniia; Dorvaux, O; Gall, B; Dechery, F; Faure, H; Yeremin, AV; Chelnokov, ML; Chepigin, VI; Isaev, AV; Izosimov, IN; Katrasev, DE; Kuznetsov, AN; Kuznetsova, AA; Malyshev, ON; Popeko, AG; Sokol, EA; Svirikhin, AI; Piot, J; Rubert, J

doi:10.1140/epja/i2014-14132-8

Fine structure in the alpha decay of U-224

Author:

Lopez-Martens, A

Hauschild, K ; Rezynkina, Kseniia ; Dorvaux, O ; Gall, B ; Dechery, F ; Faure, H ; Yeremin, AV ; Chelnokov, ML ; Chepigin, VI ; Isaev, AV ; Izosimov, IN ; Katrasev, DE ; Kuznetsov, AN ; Kuznetsova, AA ; Malyshev, ON ; Popeko, AG ; Sokol, EA ; Svirikhin, AI ; Piot, J ; Rubert, J

Keywords:

Science & Technology, Physical Sciences, Physics, Nuclear, Physics, Particles & Fields, Physics, NUCLEI, 0202 Atomic, Molecular, Nuclear, Particle and Plasma Physics, Nuclear & Particles Physics, 5106 Nuclear and plasma physics, 5107 Particle and high energy physics, 5110 Synchrotrons and accelerators

Abstract:

224U nuclei were populated in fusion-evaporation reactions using a 206Pb target and an intense 22Ne beam. Fusion-evaporation residues were separated by the new separator SHELS at the FLNR, Dubna and implanted into a large-area double-sided silicon strip detector. Position- and time-correlated alpha decays were used to identify evaporation residues. A new α-decay line at 8095(11) keV was observed in this work and assigned as the decay from 224U to the first excited 2+ in the daughter nucleus 220Th. Coincident photons were also observed allowing to unambiguously determine the excitation energy of the first excited 2+ state in 220Th to be 386.5(1) keV and not 373.3(1)keV as previously reported. The half-life of 224U was measured to be 396(17)μs.