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The Wide-field X-ray Telescope (WXT) on board the Einstein Probe (EP) produces a large postdetection candidate stream in which genuine astrophysical sources coexist with instrumental artifacts and cosmic-ray events. We present M-EPDet, a three-step postdetection framework for real-time candidate vetting in EP-WXT lobster-eye micropore optics (MPO) data. The framework combines a ResNet-based arm filter, a dual-branch temporal─spectral cosmic-ray filter, and a background-aware Bayesian Blocks module for single-exposure variability screening. Using on-orbit EP-WXT observations, we report decoupled metrics for the cascading system. M-EPDet achieves a real─bogus recall of 98.31% (98.53% × 99.78%) for genuine astrophysical sources, together with rejection rates of 92.99% for instrumental artifacts and 98.18% for cosmic-ray events. In the final step, the Bayesian Blocks module flags 0.75% of the postfiltration observations, corresponding to a 99.25% reduction in candidate volume. The system is deployed in the EP-WXT pipeline as a lightweight real-time service, reducing the manual-inspection burden in candidate vetting.

We present a comprehensive multiwavelength analysis of the long-duration gamma-ray burst (GRB) 250424A. Our dataset spans from the prompt gamma-ray emission to late-time optical monitoring, including spectra obtained with the Keck 10 m telescope. We find that the afterglow light curves display a prominent, simultaneous shallow decay phase in both X-ray and optical bands, followed by an achromatic transition to a standard decay regime. The broadband spectral energy distributions are well modeled by a single power-law function, indicating a common synchrotron origin for the emission across frequencies. We interpret the afterglow evolution within the framework of a relativistic forward shock refreshed by continuous energy injection. This scenario successfully reproduces the observed temporal and spectral behavior, yielding an isotropic equivalent kinetic energy of E<SUB>K,iso</SUB> ≍ 5.5 × 10<SUP>52</SUP> erg and an injection index of q ≍ 0.34 in a constant-density circumburst environment. The shallow decay phase is consistent with sustained energy injection lasting ∼9 ks. Despite the relatively low redshift, late-time optical observations reveal no distinct supernova component; however, our derived upper limits do not strictly rule out the presence of a typical GRB-associated supernova.