Revealing a multi-zone circumnuclear dust response in UGC 11487 through phase-resolved WISE W1--W2 diagnostics

Mid-infrared (MIR) flares trace dust reprocessing in obscured tidal disruption event (TDE) candidates, especially when the primary optical or ultraviolet flare is weak, missed, or strongly obscured. We investigate the phase-dependent W1--W2 evolution of the MIR-selected TDE candidate UGC 11487 (WTP14adeqka) and test whether its infrared behavior can be described by a single self-similar MIR response or requires a structured circumnuclear dust response. For the first time, we performed a phase-resolved analysis of the WISE/NEOWISE W1--W2 evolution of UGC 11487 (WTP14adeqka) over 2014--2024. We combined empirical W1--W2 timing, color, and flux diagnostics with phenomenological modeling and axisymmetric dust radiative-transfer calculations driven by hydrodynamically motivated fallback histories. We also constructed an aperture-matched ultraviolet-to-radio spectral energy distribution of the host galaxy. UGC 11487 exhibits a decade-long MIR flare characterized by a delayed and broader W2 response, color hysteresis, and systematic cooling from sim900 K to sim500--600 K. Observed-window positive-fluence centroids give a W2--W1 centroid offset of Δ t_ ̊m cent =224 d, corresponding to an effective differential response scale of 0.188 $, and the integrated IR energy is $(2.9--3.8) pc. The effective infrared luminosity reaches erg s -1 erg. A single fixed-color phenomenological component is strongly disfavored ( =281.7$); the preferred compact description is a two-component phenomenological model. Two physical dust-echo solutions with different fallback histories reproduce the broad W1 and $W2 light-curve evolution through compact and extended dust populations. The host is a moderately star-forming isolated barred disk, modeled under an absent or weak persistent active galactic nucleus assumption. ̊m BIC The MIR evolution suggests an obscured TDE-like accretion transient reprocessed by a spatially and thermally distributed dust population. Phase-resolved WISE diagnostics constrain differential interband response scales, while radiative-transfer modeling connects the observed evolution to the source history and dust geometry. The two-band data admit multiple physical solutions.