Computational Challenges in Nuclear and Many-­Body Physics

Coupled channel analysis in nuclear structure

Not scheduled

1m

132:028 (Nordita, Stockholm)

Speaker

Prof. Doru S. Delion (Horia Hulubei National Institute of Physics and Nuclear Engineering, POB MG-6, Bucharest, Romania)

Description

Nuclear structure is better understood in terms of interacting building blocks. As the first example we discuss the coupled channel Quasiparticle Random Phase Approximation (ccQRPA) for even-even deformed nuclei [1]. The basic building blocks are particle states coupled with the Wigner function to a given total spin. In this way, we are able to describe collective excitations in deformed nuclei by using building blocks with good angular momentum in the laboratory system. We obtain a system of coupled QRPA equations with different multipolarities. An application to E2 transitions shows a significant improvement for the well deformed region in comparison to the standard QRPA. Several applications are proposed. As a second example we describe electromagnetic and alpha transitions in even-even nuclei by using a common approach for spherical, transitional and deformed nuclei [2]. We use projected coherent states to describe the structure of daugher nuclei and a quadrupole-quadrupole alpha-core interaction to compute decay widths to excited states. It turns out that the strength of this interaction, reproducing alpha trasitions to $2^+$ states, is proportional to the clustering probability. Predictions for electromagnetic and alpha transitions to excited state are made for all available even-even emitters. The coupled channel analysis for unfavored alpha transitions in odd mass nuclei is proposed as a promising tool to investigate nuclear structure by the using both spectroscopic and alpha decay data. [1] D.S. Delion, J. Suhonen, Physical Review C87, 024309 (2013). [2] D.S. Delion, A. Dumitrescu, Physical Review C87, 044314 (2013).