Entry-level spin distributions and relative γ -neutron branching ratios of samarium isotopes populated by the (p,t) reaction

Cooper, N.; Beausang, C. W.; Humby, P.; Simon, A.; Burke, J. T.; Hughes, R. O.; Ota, S.; Reingold, C.; Saastamoinen, A.; Wilson, E.

doi:10.1103/PhysRevC.98.044618

Title: Entry-level spin distributions and relative $γ$ -neutron branching ratios of samarium isotopes populated by the $(p, t)$ reaction

Journal Article · 23 October 2018 · Physical Review C

DOI: https://doi.org/10.1103/PhysRevC.98.044618 · OSTI ID:1482823

Cooper, N. ^[1]; Beausang, C. W. ^[2]; Humby, P. ^[3]; Simon, A. ^[4]; Burke, J. T. ^[5]; Hughes, R. O. ^[5]; Ota, S. ^[5]; Reingold, C. ^[4]; Saastamoinen, A. ^[6]; Wilson, E. ^[2]

Univ. of Notre Dame, IN (United States). Dept. of Physics. Joint Inst. for Nuclear Astrophysics; Univ. of Richmond, VA (United States). Dept. of Physics; University of Notre Dame
Univ. of Richmond, VA (United States). Dept. of Physics
Univ. of Richmond, VA (United States). Dept. of Physics; Univ. of Surrey, Guildford (United Kingdom). Dept. of Physics
Univ. of Notre Dame, IN (United States). Dept. of Physics. Joint Inst. for Nuclear Astrophysics
Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Nuclear and Chemical Sciences Division
Texas A & M Univ., College Station, TX (United States). Cyclotron Inst.

The spin distribution populated in the $$^{150}\mathrm{Sm}(p,t)$$ reaction with 25 MeV protons has been investigated here using the silicon telescope and high-purity germanium array Hyperion. Angular distributions of outgoing tritons and relative intensities of $${\gamma}$$ rays from low-lying levels are used to deduce the initial spin distribution using statistical calculations and are compared with a semiclassical model of the $(p,t)$ reaction. Experimental and theoretical results suggest a peak strength near $$4{\hbar}$$ when gated on outgoing tritons detected in Hyperion, while the full $$4{\pi}$$ distribution may peak near $$2{\hbar}$$. Additionally, the average $${\gamma}$$-neutron branching ratio is determined from the data with the aid of one of two new codes presented in this work. Finally, the analysis is extended to other recent studies of $$^{152,154}\mathrm{Sm}(p,t)$$ to form systematics of the spin-dependence of the surrogate method applied to heavy nuclei in the transitional to deformed region.

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Research Organization:: Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Univ. of Notre Dame, IN (United States); Univ. of Richmond, VA (United States)

Sponsoring Organization:: USDOE National Nuclear Security Administration (NNSA)

Grant/Contract Number:: AC52-07NA27344; NA0002914; NA0003780; NA0003841

OSTI ID:: 1482823

Journal Information:: Physical Review C, Journal Name: Physical Review C Journal Issue: 4 Vol. 98; ISSN 2469-9985

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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