The origin of the neutron skin thickness, measured by the CREX and PREX collaborations as thin for ⁴⁰Ca and thick for ²⁸Pb, remains a mystery. We investigate the effects of tensor and nonlinear isovector–isoscalar terms in a relativistic mean-field model (RMF) on the properties of finite nuclei and nuclear matter. Tensor couplings are crucial for better quality binding energies of finite nuclei and charge radii for relatively heavy nuclei. However, for light nuclei, the tensor terms cannot improve the compatibility of charge radius predictions by the RMF model with experimental data. We find that parameter sets with a larger nonlinear isovector–isoscalar parameter, particularly ${\eta }_{2\rho }$ = 0.028, agree better with experimental data for Δ$r_{np}$ across light, medium, and heavy isotope chains. Using PT28, we calculate Δ$r_{np}$ for ²⁰⁸Pb as 0.214 fm, J as 33.078, and L as 58.426. Δ$r_{np}$ for ²⁰⁸Pb obtained using PT28 is consistent with the PREX-II data. Moreover, the corresponding values of J and L agree with the low L constraints. Meanwhile, the canonical mass radius predicted by PT28 aligns with the mass and radius data from the NICER collaboration. The combination of tensor and nonlinear isovector–isoscalar couplings in the RMF model provides accurate predictions for finite nuclei binding energies and relatively heavy nuclei charge radii, resulting in relatively thick Δ$r_{np}$ values for ²⁰⁸Pb without substantial L values.

^{由 CREX 和 PREX 合作测量的中子皮厚度的起源， 40} Ca为薄层， ²⁸ Pb 为厚层，仍然是个谜。我们研究相对论平均场模型 (RMF) 中张量和非线性等矢量-等标量项对有限核和核物质性质的影响。张量耦合对于有限核的更好质量的结合能和相对重的核的电荷半径至关重要。然而，对于轻核，张量项不能提高RMF模型的电荷半径预测与实验数据的兼容性。我们发现参数集具有较大的非线性等向量-等标量参数，特别是${\eta }_{2\rho }$= 0.028，与 Δ 的实验数据吻合较好$r_{np}$跨越轻、中、重同位素链。使用 PT28，我们计算 Δ$r_{np}$208 Pb 为 0.214 fm，J为 33.078，L^为58.426。Δ$r_{np}$使用 PT28获得的²⁰⁸ Pb 与 PREX-II 数据一致。此外， J和L的相应值符合低L约束。同时，PT28 预测的规范质量半径与 NICER 合作的质量和半径数据一致。RMF 模型中张量和非线性等矢量-等标量耦合的组合为有限的原子核结合能和相对较重的原子核电荷半径提供了准确的预测，从而产生相对较厚的 Δ$r_{np}$²⁰⁸ Pb的值，没有实质性的L值。