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Description of nuclear photoexcitation by Lorentzian expressions for electric dipole photon strength function

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 نشر من قبل Oleksandr Gorbachenko
 تاريخ النشر 2019
  مجال البحث
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The description of photoabsorption cross-sections of cold nuclei by closed-form Lorentzian models of photon strength functions for photoexcitation by electric dipole gamma-rays is considered. Systematics of the GDR parameters are given and input parameters of different analytical models are discussed The experimental data are compared with theoretical calculations for even-even nuclei using criteria of minimum of both least-square value and root-mean-square deviation factor. Simple extensions of the models with energy-dependent widths to high gamma-ray energies $gtrsim $ 30MeV which hold the energy-weighted sum rule for E1 gamma-transitions in good approximation are proposed and tested.



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