Near-barrier photofission in Th232 and U238

Silano, J. A.; Karwowski, H. J.

doi:10.1103/PhysRevC.98.054609

Title: Near-barrier photofission in ${}^{232}{Th}$ and ${}^{238}U$

Journal Article · Mon Nov 19 00:00:00 EST 2018 · Physical Review C

DOI:https://doi.org/10.1103/PhysRevC.98.054609· OSTI ID:1489469

Silano, J. A. ^[1]; Karwowski, H. J. ^[2]

Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States). Nuclear and Chemical Sciences Division; Triangle Universities Nuclear Lab., Durham, NC (United States); Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Physics and Astronomy
Triangle Universities Nuclear Lab., Durham, NC (United States); Univ. of North Carolina, Chapel Hill, NC (United States). Dept. of Physics and Astronomy

A study of photofission of Th-232 and U-238 was performed by using quasimonoenergetic, linearly polarized γ-ray beams from the High Intensity γ-ray Source at Triangle Universities Nuclear Laboratory. The prompt-photofission neutron polarization asymmetries, neutron multiplicities, and the photofission cross sections were measured in the near-barrier energy range of 4.3 to 6.0 MeV. This data set constitutes the lowest energy measurements of those observables to date using quasimonoenergetic photons. Large polarization asymmetries are observed in both nuclei, consistent with the E1 excitation as observed by another measurement of this kind made in a higher-energy range. Previous experimental evidence of a deep third minimum in the U-238 fission barrier has been identified as an accelerator-induced background.

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Research Organization:: Lawrence Livermore National Laboratory (LLNL), Livermore, CA (United States); University of North Carolina, Chapel Hill, NC (United States); Triangle Universities Nuclear Lab., Durham, NC (United States)

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

Grant/Contract Number:: AC52-07NA27344; FG02-97ER41033; FG02-97ER41041

OSTI ID:: 1489469

Alternate ID(s):: OSTI ID: 1482760; OSTI ID: 1658814; OSTI ID: 1658960

Report Number(s):: LLNL-JRNL-754505; 941284

Journal Information:: Physical Review C, Vol. 98, Issue 5; ISSN 2469-9985

Publisher:: American Physical Society (APS)Copyright Statement

Country of Publication:: United States

Language:: English

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Cited by: 8 works

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