Deformation dependence of the isovector giant dipole resonance: The neodymium isotopic chain revisited

L. M. Donaldson; C. A. Bertulani; J. Carter; V. O. Nesterenko; P. von Neumann-Cosel; R. Neveling; P. -G. Reinhard; I. T. Usman; P. Adsley; J. W. Brummer; E. Z. Buthelezi; G. R. J. Cooper; R. W. Fearick; S. V. Förtsch; H. Fujita; Y. Fujita; M. Jingo; W. Kleinig; C. O. Kureba; J. Kvasil; M. Latif; K. C. W. Li; J. P. Mira; F. Nemulodi; P. Papka; L. Pellegri; N. Pietralla; V. Yu. Ponomarev; A. Richter; E. Sideras-Haddad; F. D. Smit; G. F. Steyn; J. A. Swartz; A. Tamii

arXiv · 1612.06819

Deformation dependence of the isovector giant dipole resonance: The neodymium isotopic chain revisited

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Abstract

Proton inelastic scattering experiments at energy E_p = 200 MeV and a spectrometer scattering angle of 0 degree were performed on 144,146,148,150Nd and 152Sm exciting the IsoVector Giant Dipole Resonance (IVGDR). Comparison with results from photo-absorption experiments reveals a shift of resonance maxima towards higher energies for vibrational and transitional nuclei. The extracted photo-absorption cross sections in the most deformed nuclei, 150Nd and 152Sm, exhibit a pronounced asymmetry rather than a distinct double-hump structure expected as a signature of K-splitting. This behaviour can be related to the proximity of these nuclei to the critical point of the phase shape transition from vibrators to rotors with a soft quadrupole deformation potential. Self-consistent random-phase approximation (RPA) calculations using the SLy6 Skyrme force provide a relevant description of the IVGDR shapes deduced from the present data

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L. M. Donaldson, C. A. Bertulani, J. Carter, V. O. Nesterenko, P. von Neumann-Cosel, R. Neveling, P. -G. Reinhard, I. T. Usman, P. Adsley, J. W. Brummer, E. Z. Buthelezi, G. R. J. Cooper, R. W. Fearick, S. V. Förtsch, H. Fujita, Y. Fujita, M. Jingo, W. Kleinig, C. O. Kureba, J. Kvasil, M. Latif, K. C. W. Li, J. P. Mira, F. Nemulodi, P. Papka, L. Pellegri, N. Pietralla, V. Yu. Ponomarev, A. Richter, E. Sideras-Haddad, F. D. Smit, G. F. Steyn, J. A. Swartz, A. Tamii. 2017-11-03. Deformation dependence of the isovector giant dipole resonance: The neodymium isotopic chain revisited. https://arxiv.org/abs/1612.06819

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