Collectivity in Heavy Nuclei in the Shell Model Monte Carlo Approach

Autor: Özen, C., Alhassid, Y., Nakada, H.
Rok vydání: 2013
Předmět:
Druh dokumentu: Working Paper
DOI: 10.1051/epjconf/20136900011
Popis: The microscopic description of collectivity in heavy nuclei in the framework of the configuration-interaction shell model has been a major challenge. The size of the model space required for the description of heavy nuclei prohibits the use of conventional diagonalization methods. We have overcome this difficulty by using the shell model Monte Carlo (SMMC) method, which can treat model spaces that are many orders of magnitude larger than those that can be treated by conventional methods. We identify a thermal observable that can distinguish between vibrational and rotational collectivity and use it to describe the crossover from vibrational to rotational collectivity in families of even-even rare-earth isotopes. We calculate the state densities in these nuclei and find them to be in close agreement with experimental data. We also calculate the collective enhancement factors of the corresponding level densities and find that their decay with excitation energy is correlated with the pairing and shape phase transitions.
Comment: 6 pages, 3 figures, to be published in the Proceedings of the Fourth International Workshop on Compound-Nuclear Reactions and Related Topics (CNR*13)
Databáze: arXiv