A Ring of Fire Orphan γ-Ray Flare in the Neutrino Candidate 3C 120

We present 43,GHz VLBI observations of the radio galaxy 3C~120 during its brightest $\gamma$-ray outburst (March 2018), recently associated with the IceCube neutrino alert IC-180213A. Despite reaching $L_{\gamma }=3.7\times {10}^{44}$,erg,s${}^{-1}$, contemporaneous X-ray monitoring from INTEGRAL/ISGRI, MAXI/GSC, and $\mathit{\text{Swift}}$/XRT revealed no variability across 0.3-200,keV, nor in B, V, R, and I band optical observations or 37 & 235,GHz observations, establishing an orphan flare. High-cadence VLBI imaging identified a new jet disturbance (N) propagating at ${\beta }_{\mathrm{a}\mathrm{p}\mathrm{p}}=(2.8\pm 1.3)$ through quasi-stationary features C1-C3. The $\gamma$-ray peak coincided spatially and temporally with N crossing C3 ($r\sim 0.38$,mas), where we measured a factor-of-5 increase in fractional polarization ($m=16\mathrm{\%}$) and $\mathrm{\Delta }\chi \sim {24}^{\circ }$ EVPA rotation, indicating localized magnetic field compression. The extreme Compton dominance ($L_{\gamma }\mathrm{/}{L}_{\mathrm{s}\mathrm{y}\mathrm{n},\mathrm{b}\mathrm{l}\mathrm{o}\mathrm{b}}\approx 160$) is naturally explained by the Ring of Fire scenario, in which N (${\mathrm{\Gamma }}_{\mathrm{b}\mathrm{l}\mathrm{o}\mathrm{b}}=6$, $B_{\mathrm{b}\mathrm{l}\mathrm{o}\mathrm{b}}=0.023$,G) inverse-Compton scatters synchrotron photons from C3, reproducing the observed $\gamma$-ray luminosity for physically reasonable parameters. Unlike the 2014-2015 orphan flares attributed to rapid spine reorientation near the BLR, the 2018 event represents a distinct physical mechanism, a propagating disturbance interacting with stationary jet structure at $\sim 10\times$ the BLR radius.This work provides the first direct observational link between VLBI-resolved jet dynamics and orphan $\gamma$-ray emission in a radio galaxy.