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arXiv · 2306.04036

Five-body calculation of $s$-wave $n$-$^4$He scattering at next-to-leading order pionless effective field theory

Mirko Bagnarol·Martin Schäfer·Betzalel Bazak·Nir Barnea
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Abstract

We present the first five-body calculations of $s$-wave $n$-$^4$He scattering within leading order and next-to-leading order (NLO) pionless effective field theory. Using an harmonic oscillator trap technique and pionless effective field theory fitted to just six well-established experimental parameters, we predict the $s$-wave $n$-$^4$He phase shifts, scattering length $a^{1/2}_{n ^4\text{He}}(\text{NLO})=2.47(4\ \text{num.})~(17\ \text{theor.})~{\rm fm}$, and effective range $r^{1/2}_{n ^4\text{He}}(\text{NLO})=1.384(3\ \text{num.})~(211\ \text{theor.})~{\rm fm}$ in agreement with experiment. The apparent cutoff independence of our results is used to estimate the theoretical errors coming as an integral part of our final results.

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Mirko Bagnarol, Martin Schäfer, Betzalel Bazak, Nir Barnea. 2023-06-06. Five-body calculation of $s$-wave $n$-$^4$He scattering at next-to-leading order pionless effective field theory. https://doi.org/10.1016/j.physletb.2023.138078

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