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arXiv · 2506.06629

Charge symmetry breaking effects of $\omega$-$\rho^0$ mixing in relativistic mean-field model

Yusuke Tanimura·Tomoya Naito·Hiroyuki Sagawa·Myung-Ki Cheoun
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Abstract

We present a relativistic mean-field model that incorporates charge symmetry breaking (CSB) of nuclear force via $ \omega $-$ \rho^0 $ meson mixing, along with corrections to the electromagnetic interaction including the nucleon form factors, first-order vacuum polarization, and Coulomb exchange and pairing terms. The model parameters are refitted using the mass differences of $ T = 1/2 $ mirror nuclei and ground-state properties of magic nuclei, yielding DD-ME-CSB parameter set. The DD-ME-CSB parameter set reproduces the mass differences of mirror nuclei reasonably well up to $ T = 2 $, demonstrating the importance of $ \omega $-$ \rho^0 $ mixing. A connection of the present model to a Skyrme-type CSB interaction is also established through a gradient expansion of the energy density functional.

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Yusuke Tanimura, Tomoya Naito, Hiroyuki Sagawa, Myung-Ki Cheoun. 2025-06-07. Charge symmetry breaking effects of $\omega$-$\rho^0$ mixing in relativistic mean-field model. https://doi.org/10.1140/epja%2Fs10050-025-01699-y

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