Physics Letters B (Dec 2015)

Stellar 30-keV neutron capture in 94, 96Zr and the Zr90(γ,n)Zr89 photonuclear reaction with a high-power liquid-lithium target

  • M. Tessler,
  • M. Paul,
  • A. Arenshtam,
  • G. Feinberg,
  • M. Friedman,
  • S. Halfon,
  • D. Kijel,
  • L. Weissman,
  • O. Aviv,
  • D. Berkovits,
  • Y. Eisen,
  • I. Eliyahu,
  • G. Haquin,
  • A. Kreisel,
  • I. Mardor,
  • G. Shimel,
  • A. Shor,
  • I. Silverman,
  • Z. Yungrais

DOI
https://doi.org/10.1016/j.physletb.2015.10.058
Journal volume & issue
Vol. 751, no. C
pp. 418 – 422

Abstract

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A high-power Liquid-Lithium Target (LiLiT) was used for the first time for neutron production via the thick-target Li7(p,n)Be7 reaction and quantitative determination of neutron capture cross sections. Bombarded with a 1–2 mA proton beam at 1.92 MeV from the Soreq Applied Research Accelerator Facility (SARAF), the setup yields a 30-keV quasi-Maxwellian neutron spectrum with an intensity of 3–5×1010 n/s, more than one order of magnitude larger than present near-threshold Li7(p,n) neutron sources. The setup was used here to determine the 30-keV Maxwellian averaged cross section (MACS) of 94Zr and 96Zr as 28.0±0.6 mb and 12.4±0.5 mb respectively, based on activation measurements. The precision of the cross section determinations results both from the high neutron yield and from detailed simulations of the entire experimental setup. We plan to extend our experimental studies to low-abundance and radioactive targets. In addition, we show here that the setup yields intense high-energy (17.6 and 14.6 MeV) prompt capture γ rays from the Li7(p,γ)Be8 reaction with yields of ∼3×108γs−1mA−1 and ∼4×108γs−1mA−1, respectively, evidenced by the Zr90(γ,n)Zr89 photonuclear reaction.

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