arXiv 1812.090722018-12-21nucl-exnucl-th

Gamma strength functions and the Brink-Axel hypothesis

Peter von Neumann-Cosel

备注：: 9 pages, 6 figures, Invited talk presented at the 6th International Workshop on Compound-Nuclear Reactions and Related Topics, Berkeley, USA, September 24-28, 2018

英文摘要：

Experimental tests of the Brink-Axel hypothesis relating gamma strength functions (GSF) deduced from absorption and emission experiments are discussed. High-resolution inelastic proton scattering at energies of a few hundred MeV and at very forwrd angles including $0^\circ$ presents a new approach to test the validity of the BA hypothesis in the energy region of the pygmy dipole resonance. Such data not only provide the GSF but also the level density and thus permit an independent test of their model-dependent decomposition in the Oslo method.

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