Orce, Nico2023-03-062023-03-062015Orce, N. (2015). New formulas for the (−2) moment of the photoabsorption cross section, σ−2. Physical Review C, 91 (6). 10.1103/PhysRevC.91.0646022469-999310.1103/PhysRevC.91.064602http://hdl.handle.net/10566/8535Two new formulas for the (−2) moment of the photoabsorption cross section, σ−2, have been determined, respectively, from the 1988 photoneutron evaluation of Dietrich and Berman and a mass-dependent symmetry energy coefficient, asym(A). The data for A 50 follow, with a RMS deviation of 6%, the power law σ−2 = 2.4A5/3 μb/MeV, which is in agreement with Migdal’s calculation of σ−2 = 2.25A5/3 μb/MeV based on the hydrodynamic model and the σ−2 sum rule. The additional inclusion of asym(A) provides a deeper insight into the nuclear polarization of A 10 nuclei.enPhysicsNuclear polarizationEnergyArticle