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arXiv · 2002.04111

Threshold expansion formula of $N$-boson in finite volume from variational approach

Peng Guo
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Abstract

In present work, we show how the threshold expansion formula of $N$ identical bosons in finite volume may be derived by iterations of Faddeev-type coupled dynamical equations. The energy shift of $N$-boson system near threshold is dominated by zero momenta mode of $N$-body amplitudes with all particles nearly static. The dominant zero momenta mode and sub-leading non-zero momenta mode contributions are connected through finite volume Faddeev-type coupled dynamical equations. Eliminating non-zero momenta modes by iterations ultimately yields an analytic expression that can be solved by threshold expansion.

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BibTeXRIS

Peng Guo. 2020-02-10. Threshold expansion formula of $N$-boson in finite volume from variational approach. https://doi.org/10.1103/physrevd.101.054512

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