In this work, I present new extractions of the proton's $\langle r_{Ep}\rangle$ and neutron's $\langle r_{En}^2\rangle$ conventional charge radii. This analysis is based on two-photon-exchange (TPE) corrected elastic electron-proton cross section ${\sigma }_R$ data from the Mainz experiment, covering the range $0.0155\le Q^2\le 1.0{\mathrm{GeV}}^2$, and updated neutron electric $G_E^n\left(Q^2\right)$ data spanning $0.00973\le Q^2\le 3.410{\mathrm{GeV}}^2$. Both $G_E^{(p,n)}\left(Q^2\right)$ form factors were fit independently using various functional forms and parametrizations that enforce proper low-$Q^2$ constraints. Charge radii were extracted from fits over multiple $Q^2$ intervals, with final values obtained from statistically stable regions. The resulting proton charge radius $\langle r_{Ep}\rangle =0.853\pm 0.{001}_{\text{(stat.)}}\pm 0.{001}_{\text{(sys.)}}\mathrm{fm}$ is consistent with both PRad I and muonic hydrogen results, and falls within the range of values reported in recent reanalyses. The neutron charge radius $\langle r_{En}^2\rangle =-0.106\pm 0.{003}_{\text{(stat.)}}\pm 0.{002}_{\text{(sys.)}} {\mathrm{fm}}^2$ also agrees with modern determinations. Additionally, the charge radii of the baryonic core (three valence quarks) and quark-antiquark meson cloud components of the nucleon are extracted. My results support the $1/2$-fermi size scale of the baryonic core, and $0.617\mathrm{fm}$ of the mesonic cloud of the nucleon, in good agreement with lattice QCD calculations based on dispersion relations and the functional spectral analysis approach. The flavor-separated mean-squared transverse charge distributions of the up- and down-quark $\langle b_{(u,d)}^2\rangle$ radii are also studied, revealing subtle but non-negligible differences in their spatial extent.

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• Form factors
• Nuclear radii
• Nucleon-nucleon interactions
• Particle interactions
• QCD in nuclear reactions