Microscopic Calculation of Nuclear Level Densities with Auxiliary-Fields Monte Carlo Method

Microscopic Nuclear Level Densities from Fe to Ge by the Shell Model Monte Carlo Method

We calculate microscopically total and parity-projected level densities for β-stable even-even nuclei between Fe and Ge, using the shell model Monte Carlo methods in the complete (pf +0g9/2)-shell. A single-particle level density parameter a and backshift parameter ∆ are extracted by fitting the calculated densities to a backshifted Bethe formula, and their systematics are studied across the re...

Microscopic calculation of symmetry projected nuclear level densities

We present a quantum Monte Carlo method with exact projection on parity and angular momentum that is free of sign-problems for seniority-conserving nuclear interactions. This technique allows a microscopic calculation of angular momentum and parity projected nuclear level densities. We present results for the 55Fe, 56Fe and 57Fe isotopes. Signatures of the pairing phase transition are observed ...

Particle-Number Reprojection in the Shell Model Monte Carlo Method: Application to Nuclear Level Densities

We introduce a particle-number reprojection method in the shell model Monte Carlo that enables the calculation of observables for a series of nuclei using a Monte Carlo sampling for a single nucleus. The method is used to calculate nuclear level densities in the complete (pf + g9/2)-shell using a good-sign Hamiltonian. Level densities of odd-A and odd-odd nuclei are reliably extracted despite a...

Total and Parity-Projected Level Densities of Iron-Region Nuclei in the Auxiliary Fields Monte Carlo Shell Model

We use the auxiliary-fields Monte Carlo method for the shell model in the complete (pf + 0g9/2)-shell to calculate level densities. We introduce parity projection techniques which enable us to calculate the parity dependence of the level density. Results are presented for 56Fe, where the calculated total level density is found to be in remarkable agreement with the experimental level density. T...

The Auxiliary Field Diffusion Monte Carlo Method for Nuclear Physics and Nuclear Astrophysics