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arXiv · 2311.11438

Magnetic dipole transition in $^{48}$Ca

B. Acharya·B. S. Hu·S. Bacca·G. Hagen·P. Navrátil·T. Papenbrock
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Abstract

The magnetic dipole transition strength $B(M1)$ of $^{48}$Ca is dominated by a single resonant state at an excitation energy of 10.23 MeV. Experiments disagree about $B(M1)$ and this impacts our understanding of spin flips in nuclei. We performed ab initio computations based on chiral effective field theory and found that $B(M1:0^+\rightarrow1^+)$ lies in the range from $7.0$ to $10.2~\mu_N^2$. This is consistent with a $(\gamma,n)$ experiment but larger than results from $(e,e^\prime)$ and $(p,p')$ scattering. Two-body currents yield no quenching of the $B(M1)$ strength and continuum effects reduce it by about 10%. For a validation of our approach, we computed magnetic moments in $^{47,49}$Ca and performed benchmark calculations in light nuclei.

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B. Acharya, B. S. Hu, S. Bacca, G. Hagen, P. Navrátil, T. Papenbrock. 2023-11-19. Magnetic dipole transition in $^{48}$Ca. https://doi.org/10.1103/physrevlett.132.232504

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