Abstract
The nuclear reaction photon strength function (PSF) is defined as the product of a level density formulation (LDF) and a γ-ray strength function (GSF). The photonuclear reaction PSF is completely described by a standard Lorentzian (SLO) built on the Giant Dipole Resonance (GDR) using the Brink-Axel (BA) formulation. Photonuclear data can be deconvoluted into a predominantly E1 photoexcitation GSF that decreases nearly exponentially from ≈10−8 MeV−2 at Eγ = 2 MeV to between ≈10−14 − 10−19 MeV−2 at Eγ = 25 MeV. Other reaction PSFs cannot be described by BA because they include M1 and E2 transitions that may not be described by the SLO formulation. In this work GSFs for 92−98Mo have been deconvoluted from Oslo reaction data by removing the measured level density dependence from their PSFs. For each nuclide both significant low and high-energy GSF enhancements are observed.
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Acknowledgements
This work was performed under the auspices of the U.S. Department of Energy by the University of California, supported by the Director, Office of Science, Office of Basic Energy Sciences, of the U.S. Department of Energy at Lawrence Berkeley National Laboratory under Contract No. DE-AC02-05CH11231. I especially wish to thank my colleagues at the University of Oslo for our many scientific discussions and their hospitality during my many visits there that inspired my interest in this subject.
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Firestone, R.B. (2021). Deconvolution of the Photon Strength Function. In: Escher, J., et al. Compound-Nuclear Reactions . Springer Proceedings in Physics, vol 254. Springer, Cham. https://doi.org/10.1007/978-3-030-58082-7_21
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DOI: https://doi.org/10.1007/978-3-030-58082-7_21
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