A path integral Monte Carlo method for the quasielastic response

Citation

Carraro, Carlo (1990) A path integral Monte Carlo method for the quasielastic response. Dissertation (Ph.D.), California Institute of Technology. http://resolver.caltech.edu/CaltechETD:etd-06072007-080221

Abstract

We formulate the quasielastic response of a non-relativistic many-body system at zero temperature in terms of ground state density matrix elements and real time path integrals that embody the final state interactions. While the former provide the weight for a conventional Monte Carlo calculation, the latter require a more sophisticated treatment. We argue that the recently developed Stationary Phase Monte Carlo technique can be used to study the approach to "Y-scaling." We perform calculations for a particle in a potential well in one and three dimensions and compare them to the exact results available for these models. We then derive an eikonal approximation to the Path Integrals. This method is suitably generalized to treat strongly repulsive interactions, and allows comparison to Silver's theory of final state interactions in a straightforward way. We also give an exact prescription to calculate the scaling limit for potentials comprising a hard core. Finally, we study the approach to scaling in a model 4He nucleus, and find good agreement with experimental data.

Thesis Files