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arXiv · 2405.09799

Direct ab initio calculation of the $^{4}$He nuclear electric dipole polarizability

Peng Yin·Andrey M. Shirokov·Pieter Maris·Patrick J. Fasano·Mark A. Caprio·He Li·Wei Zuo·James P. Vary
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Abstract

The calculation of nuclear electromagnetic sum rules by directly diagonalizing the nuclear Hamiltonian in a large basis is numerically challenging and has not been performed for $A>2$ nuclei. With the significant progress of high performance computing, we show that calculating sum rules using numerous discretized continuum states obtained by directly diagonalizing the ab initio no-core shell model Hamiltonian is achievable numerically. Specifically, we calculate the $^{4}$He electric dipole ($E1$) polarizability, that is an inverse energy weighted sum rule, employing the Daejeon16 $NN$ interaction. We demonstrate that the calculations are numerically tractable as the dimension of the basis increases and are convergent. Our results for the $^{4}$He electric dipole polarizability are consistent with the most recent experimental data and are compared with those of other theoretical studies employing different techniques and various interactions.

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Peng Yin, Andrey M. Shirokov, Pieter Maris, Patrick J. Fasano, Mark A. Caprio, He Li, Wei Zuo, James P. Vary. 2024-05-16. Direct ab initio calculation of the $^{4}$He nuclear electric dipole polarizability. https://doi.org/10.1016/j.physletb.2024.138857

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