Moong, Gautam Rupak Lan Tai
Clay, R. Torsten
Date of Degree
Graduate Thesis - Open Access
Master of Science
College of Arts and Sciences
Department of Physics and Astronomy
In this thesis we study non-relativistic, low-energy, s-wave scattering in a four-body spin-1/2 fermion system. The scattering is caused by an attractive twoermion contact interaction which is capable of producing a weakly bound state known as a dimer. This fourermion system is used to study the scattering of a two-dimer system. Using Hybrid Monte Carlo methods we compute the ground state energies of the system on a lattice. Luscher’s finite-volume formula and the Effective Range Expansion are used to calculate the dimer-dimer scattering length add and effective range rdd in terms of the fermionermion scattering length aff. Using these techniques we obtain the values add=aff = 0:60 +/- 0:04 and rdd=aff = 3:2 +/- 0:5. This scattering length shows excellent agreement with the numerous values in the literature. We also compare this effective range with the only currently known value in the literature.
Katterjohn, Kristopher, "Universal Four-Fermion Interaction in Lattice Effective Field Theory" (2015). Theses and Dissertations MSU. 4849.