Calculation of meson charge radii using model-independent method in the PACS10 configuration

Abstract

We report our preliminary results for the charge radii of $\pi^{+}$ and $K^{+}$ mesons with the PACS10 configuration generated at the physical point using the Iwasaki gauge action and $N_{f}=2+1$ stout-smeared nonperturbatively $\mathcal{O}(a)$ improved Wilson quark action, especially at $0.085$ fm corresponding lattice size $128^4$. The charge radii are obtained from a model-independent method that directly calculates the first-order differential coefficient of the electromagnetic form factor and also from a traditional method that analyzes the form factor using a fit ansatz. We compare our preliminary results obtained by these methods with previous lattice calculations and experiments.