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arXiv · 1907.08091

Nuclear electric dipole moment in the cluster model with a triton: $^7$Li and $^{11}$B

Nodoka Yamanaka·Taiichi Yamada·Yasuro Funaki
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Abstract

We calculate the electric dipole moment (EDM) of the nuclei $^7$Li and $^{11}$B in the cluster model with $α$ ($^4$He) and triton ($^3$H) clusters as degrees of freedom. The $^7$Li and $^{11}$B nuclei are treated in the two- and three-body problem, respectively, using the Gaussian expansion method, assuming the one-meson exchange P, CP-odd nuclear forces. We find that $^7$Li and $^{11}$B have larger sensitivity to the CP violation than the deuteron. It is also suggested that the EDMs of $^7$Li and $^{11}$B, together with those of $^6$Li, $^9$Be and the $1/2^+_1$ excited state of $^{13}$C, obey an approximate counting rule accounting for the EDM of the cluster and the $α-N $ polarization. We show their sensitivity on the hadronic level CP violation in terms of the chiral effective field theory, and discuss their role in probing new physics beyond the standard model.

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Nodoka Yamanaka, Taiichi Yamada, Yasuro Funaki. 2019-11-06. Nuclear electric dipole moment in the cluster model with a triton: $^7$Li and $^{11}$B. https://doi.org/10.1103/physrevc.100.055501

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