Extension of the generator coordinate method with basis optimization

The generator coordinate method (GCM) has been a well-known method to describe nuclear collective motions. In this method, one specifies a priori the relevant collective degrees of freedom as input of the method, based on empirical and/or phenomenological assumptions. We here propose a new extension of the GCM, in which both the basis Slater determinants and weight factors are optimized according to the variational principle. Applying this method to 16O and 28Si nuclei with the Skyrme functional, we demonstrate that the optimized bases correspond to excited states along a collective path, unlike the conventional GCM which superposes only the local ground states. This implies that a collective coordinate for large amplitude collective motions is determined in a much more complex way than what has been assumed so far.

Automated summary

The generator coordinate method (GCM) is a well-known method for describing nuclear collective motions. We propose a new extension of the GCM, in which the basis Slater determinants and weight factors are optimized using the variational principle. By applying this method to 16O and 28Si nuclei with the Skyrme functional, we show that the optimized bases correspond to excited states along a collective path, challenging the assumption of the conventional GCM.