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arXiv · 1206.1765

Benchmark calculations for elastic fermion-dimer scattering

Shahin Bour·H. -W. Hammer·Dean Lee·Ulf-G. Meißner
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Abstract

We present continuum and lattice calculations for elastic scattering between a fermion and a bound dimer in the shallow binding limit. For the continuum calculation we use the Skorniakov-Ter-Martirosian (STM) integral equation to determine the scattering length and effective range parameter to high precision. For the lattice calculation we use the finite-volume method of L\"uscher. We take into account topological finite-volume corrections to the dimer binding energy which depend on the momentum of the dimer. After subtracting these effects, we find from the lattice calculation kappa a_fd = 1.174(9) and kappa r_fd = -0.029(13). These results agree well with the continuum values kappa a_fd = 1.17907(1) and kappa r_fd = -0.0383(3) obtained from the STM equation. We discuss applications to cold atomic Fermi gases, deuteron-neutron scattering in the spin-quartet channel, and lattice calculations of scattering for nuclei and hadronic molecules at finite volume.

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Shahin Bour, H. -W. Hammer, Dean Lee, Ulf-G. Meißner. 2012-06-08. Benchmark calculations for elastic fermion-dimer scattering. https://doi.org/10.1103/physrevc.86.034003

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