Phase histograms of gamma-ray photons for PSR J0435+3233 aligned with radio polarization profiles. Panel (A) is the result with the H-test value of H ≃  69 for the Fermi data in the FAST observation duration (MJD: 59101—60877) and folded using the timing solution A with i_x ∼ 85^∘ (see Table 3). Note that folding Fermi data from MJD 59101 to 60783 yields H ≃ 73. Panel (B) shows the result from all available Fermi data (MJD: 54684—61205 ≃18 yr) using the final improved timing solution A, with the H-test factor reaching 221. The folding results of the timing solution B with i_x ∼ 54^∘ give similar H-test values. The error bars of the Fermi profile show the 1σ uncertainties, which are the square roots of the sum of squared weights. The lower two panels show timing-aligned radio polarization profiles at 1.25 GHz, showing a half-period offset from the Fermi profile. The total intensity I (solid line), linearly polarized intensity L (dashed line), and circularly polarized emission V (dotted line), with positive values for the left-hand sense, were obtained from 20 minute FAST observations on 2022 August 6, which has the highest signal-to-noise ratio. The bottom subpanel plots the linear polarization position angles (PAs), with uncertainties of ±1σ.