Experimental level densities of atomic nuclei

M. Guttormsen , M. Aiche (1) , F. L. Bello Garrote , L. A. Bernstein , D. L. Bleuel , Y. Byun , Q. Ducasse (1) , T. K. Eriksen , F. Giacoppo , A. Görgen (2) , F. Gunsing (2) , T. W. Hagen , B. Jurado (1) , M. Klintefjord , A. C. Larsen , L. Lebois (3) , B. Leniau (3) , H. T. Nyhus , T. Renstrøm , S. J. Rose , E. Sahin , S. Siem , T. G. Tornyi , G. M. Tveten , A. Voinov , M. Wiedeking , J. Wilson (3)

1 CENBG - Centre d'Etudes Nucléaires de Bordeaux Gradignan
2 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers
3 IPNO - Institut de Physique Nucléaire d'Orsay

It is almost 80 years since Hans Bethe described the level density as a non-interacting gas of protons and neutrons. In all these years, experimental data were interpreted within this picture of a fermionic gas. However, the renewed interest of measuring level density using various techniques calls for a revision of this description. In particular, the wealth of nuclear level densities measured with the Oslo method favors the constant-temperature level density over the Fermi-gas picture. From the basis of experimental data, we demonstrate that nuclei exhibit a constant-temperature level density behavior for all mass regions and at least up to the neutron threshold.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

M. Guttormsen, M. Aiche, F. L. Bello Garrote, L. A. Bernstein, D. L. Bleuel, et al.. Experimental level densities of atomic nuclei. European Physical Journal A, 2015, 51, pp.170. ⟨10.1140/epja/i2015-15170-4⟩. ⟨in2p3-01157547⟩