Experimental level densities of atomic nuclei

Abstract

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.

8 pages, 8 figures

References in corpus (9)

• Analysis of possible systematic errors in the Oslo method
• Novel technique for constraining r-process (n,$\gamma$) reaction rates
• Spin projection in the shell model Monte Carlo method and the spin distribution of nuclear level densities
• The SiRi Particle-Telescope System
• Evidence for the pair-breaking process in 116,117Sn
• Enhanced radiative strength in the quasi-continuum of 117Sn
• Extraction of thermal and electromagnetic properties in 45Ti
• Fermi's golden rule applied to the gamma decay in the quasicontinuum of 46Ti
• Shell-gap reduced level densities in ${}^{89,90}$Y

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