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arXiv · 1302.6316

A phenomenological approach to the equation of state of a unitary Fermi gas

M. V. N. Murthy·M. Brack·R. K. Bhaduri
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Abstract

We propose a phenomenological approach for the equation of state of a unitary Fermi gas. The universal equation of state is parametrised in terms of Fermi-Dirac integrals. This reproduces the experimental data over the accessible range of fugacity and normalised temperature, but cannot describe the superfluid phase transition found in the MIT experiment \cite{ku}. The most sensitive data for compressibility and specific heat at phase transition can, however, befitted by introducing into the grand partition function a pair of complex conjugate zeros lying in the complex fugacity plane slightly off the real axis.

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M. V. N. Murthy, M. Brack, R. K. Bhaduri. 2013-02-26. A phenomenological approach to the equation of state of a unitary Fermi gas. https://doi.org/10.1007/s12043-014-0749-y

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