This report establishes a Carbon Energy Synergistic Hub (CESH) model and a carbon emission sensitivity analysis method for integrated energy systems. The model is capable of quantifying the distribution of energy flows and carbon flows across all stages of the system, including energy supply, distribution, conversion, storage, and consumption, and characterizing the coupling relationships between these flows. Furthermore, the proposed model is applied to the planning and optimal scheduling of integrated energy systems, analyzing its value in enhancing system economic efficiency and reducing carbon emissions.