Third- and fourth-order virial coefficients of harmonically trapped fermions in a semiclassical approximation

  title={Third- and fourth-order virial coefficients of harmonically trapped fermions in a semiclassical approximation},
  author={K. J. Morrell and Casey E. Berger and Joaqu{\'i}n E. Drut},
  journal={Physical Review A},
Using a leading-order semiclassical approximation, we calculate the third- and fourth-order virial coefficients of nonrelativistic spin-1/2 fermions in a harmonic trapping potential in arbitrary spatial dimensions, and as functions of temperature, trapping frequency and coupling strength. Our simple, analytic results for the interaction-induced changes $\Delta b_3$ and $\Delta b_4$ agree qualitatively, and in some regimes quantitatively, with previous numerical calculations for the unitary… 

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