Superallowed α Decay to Doubly Magic ^{100}Sn

K Auranen; D Seweryniak; M Albers; A D Ayangeakaa; S Bottoni; M P Carpenter; C J Chiara; P Copp; H M David; D T Doherty; J Harker; C R Hoffman; R V F Janssens; T L Khoo; S A Kuvin; T Lauritsen; G Lotay; A M Rogers; J Sethi; C Scholey; R Talwar; W B Walters; P J Woods; S Zhu

doi:10.1103/PhysRevLett.121.182501

Superallowed α Decay to Doubly Magic ^{100}Sn

Phys Rev Lett. 2018 Nov 2;121(18):182501. doi: 10.1103/PhysRevLett.121.182501.

Authors

K Auranen¹, D Seweryniak¹, M Albers¹, A D Ayangeakaa¹, S Bottoni¹, M P Carpenter¹, C J Chiara^{1

2}, P Copp^{1

3}, H M David¹, D T Doherty⁴, J Harker^{1

2}, C R Hoffman¹, R V F Janssens^{5

6}, T L Khoo¹, S A Kuvin^{1

7}, T Lauritsen¹, G Lotay⁸, A M Rogers¹, J Sethi^{1

2}, C Scholey⁹, R Talwar¹, W B Walters², P J Woods⁴, S Zhu¹

Affiliations

¹ Physics Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, Illinois 60439, USA.
² Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
³ Department of Physics and Applied Physics, University of Massachusetts Lowell, Lowell, Massachusetts 01854, USA.
⁴ University of Edinburgh, Edinburgh EH9 3JZ, United Kingdom.
⁵ Department of Physics and Astronomy, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
⁶ Triangle Universities Nuclear Laboratory, Duke University, Durham, North Carolina 27708, USA.
⁷ Department of Physics, University of Connecticut, Storrs, Connecticut 06269, USA.
⁸ University of Surrey, Guildford GU2 7XH, United Kingdom.
⁹ Department of Physics, University of Jyvaskyla, P.O. Box 35, FI-40014 University of Jyvaskyla, Finland.

PMID: 30444390
DOI: 10.1103/PhysRevLett.121.182501

Abstract

We report the first observation of the ^{108}Xe→^{104}Te→^{100}Sn α-decay chain. The α emitters, ^{108}Xe [E_{α}=4.4(2) MeV, T_{1/2}=58_{-23}^{+106} μs] and ^{104}Te [E_{α}=4.9(2) MeV, T_{1/2}<18 ns], decaying into doubly magic ^{100}Sn were produced using a fusion-evaporation reaction ^{54}Fe(^{58}Ni,4n)^{108}Xe, and identified with a recoil mass separator and an implantation-decay correlation technique. This is the first time α radioactivity has been observed to a heavy self-conjugate nucleus. A previous benchmark for study of this fundamental decay mode has been the decay of ^{212}Po into doubly magic ^{208}Pb. Enhanced proton-neutron interactions in the N=Z parent nuclei may result in superallowed α decays with reduced α-decay widths significantly greater than that for ^{212}Po. From the decay chain, we deduce that the α-reduced width for ^{108}Xe or ^{104}Te is more than a factor of 5 larger than that for ^{212}Po.