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On the mass formula and Wigner and curvature energy terms

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 نشر من قبل Guy Royer
 تاريخ النشر 2007
  مجال البحث
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 تأليف G. Royer




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The efficiency of different mass formulas derived from the liquid drop model including or not the curvature energy, the Wigner term and different powers of the relative neutron excess $I$ has been determined by a least square fitting procedure to the experimental atomic masses assuming a constant R$_{0,charge}$/A$^{1/3}$ ratio. The Wigner term and the curvature energy can be used independently to improve the accuracy of the mass formula. The different fits lead to a surface energy coefficient of around 17-18 MeV, a relative sharp charge radius r$_0$ of 1.22-1.23 fm and a proton form-factor correction to the Coulomb energy of around 0.9 MeV.

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