Novel ΔJ=1 Sequence in Ge78: Possible Evidence for Triaxiality

Forney, A. M.; Walters, W. B.; Chiara, C. J.; Janssens, R. V. F.; Ayangeakaa, A. D.; Sethi, J.; Harker, J.; Alcorta, M.; Carpenter, M. P.; Gurdal, G.; Hoffman, C. R.; Kay, B. P.; Kondev, F. G.; Lauritsen, T.; Lister, C. J.; McCutchan, Elizabeth A.; Rogers, A. M.; Seweryniak, D.; Stefanescu, I.; Zhu, S.

doi:10.1103/PhysRevLett.120.212501

Title: Novel $Δ J = 1$ Sequence in ${}^{78}{Ge}$ : Possible Evidence for Triaxiality

Journal Article · 22 May 2018 · Physical Review Letters

DOI: https://doi.org/10.1103/PhysRevLett.120.212501 · OSTI ID:1438428

Forney, A. M. ^[1]; Walters, W. B. ^[1]; Chiara, C. J. ^[2]; Janssens, R. V. F. ^[3]; Ayangeakaa, A. D. ^[4]; Sethi, J. ^[1]; Harker, J. ^[5]; Alcorta, M. ^[6]; Carpenter, M. P. ^[7]; Gurdal, G. ^[8]; Hoffman, C. R. ^[7]; Kay, B. P. ^[7]; Kondev, F. G. ^[7]; Lauritsen, T. ^[7]; Lister, C. J. ^[9]; McCutchan, Elizabeth A. ^[10]; Rogers, A. M. ^[9]; Seweryniak, D. ^[7]; Stefanescu, I. ^[5]; Zhu, S. ^[7]

Univ. of Maryland, College Park, MD (United States)
Univ. of Maryland, College Park, MD (United States); Argonne National Lab. (ANL), Argonne, IL (United States); U.S. Army Research Lab., Adelphi, MD (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); Univ. of North Carolina, Chapel Hill, NC (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); United States Naval Academy, Annapolis, MD (United States)
Univ. of Maryland, College Park, MD (United States); Argonne National Lab. (ANL), Argonne, IL (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); TRIUMF, Vancouver, BC (Canada)
Argonne National Lab. (ANL), Argonne, IL (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); Millsaps College, Jackson, MS (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); Univ. of Massachusetts, Lowell, MA (United States)
Argonne National Lab. (ANL), Argonne, IL (United States); Brookhaven National Lab. (BNL), Upton, NY (United States)

A sequence of low-energy levels in ^$7832$Ge₄₆ has been identified with spins and parity of 2⁺, 3⁺, 4⁺, 5⁺, and 6⁺. Decays within this band proceed strictly through ΔJ = 1 transitions, unlike similar sequences in neighboring Ge and Se nuclei. Above the 2⁺ level, members of this sequence do not decay into the groundstate band. Moreover, the energy staggering of this sequence has the phase that would be expected for a γ-rigid structure. The energies and branching ratios of many of the levels are described well by shell-model calculations. However, the calculated reduced transition probabilities for the ΔJ = 2 in-band transitions imply that they should have been observed, in contradiction with the experiment. Within the calculations of Davydov, Filippov, and Rostovsky for rigid-triaxial rotors with γ = 30°, there are sequences of higher-spin levels connected by strong ΔJ = 1 transitions which decay in the same manner as those observed experimentally, yet are calculated at too high an excitation energy.

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Research Organization:: Brookhaven National Laboratory (BNL), Upton, NY (United States); Argonne National Laboratory (ANL), Argonne, IL (United States)

Sponsoring Organization:: USDOE Office of Science (SC), Nuclear Physics (NP); USDOE Office of Science - Office of Nuclear Physics

Grant/Contract Number:: SC0012704; AC02-06CH11357; AC02-98CH10886; FG02-94ER40834; FG02-97ER41041; FG02-97ER41033

OSTI ID:: 1438428

Alternate ID(s):: OSTI ID: 1438290; OSTI ID: 1493714

Report Number(s):: BNL-203652-2018-JAAM; BNL-203358-2018-JAAM; PRLTAO; TRN: US1900437

Journal Information:: Physical Review Letters, Vol. 120, Issue 21; ISSN 0031-9007

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 15 works

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