1：Experimental Design and Method Selection:

Angle-resolved photoemission spectroscopy (ARPES) and density functional theory (DFT)-based calculations were used to study the electron–phonon coupling strength. The electron–phonon coupling parameter λ was obtained by measuring the linewidth of the spin–split bands as a function of temperature and fitting the data points using a Debye model.

2：Sample Selection and Data Sources:

Single-layer MoS2 was synthesized on Au(111) using Mo evaporation in a background pressure of H2S. ARPES spectra were acquired at the SGM-3 beamline of ASTRID2 using a photon energy of 30 eV.

3：2S. ARPES spectra were acquired at the SGM-3 beamline of ASTRID2 using a photon energy of 30 eV. List of Experimental Equipment and Materials:

3. List of Experimental Equipment and Materials: SuperESCA beamline at Elettra for sample synthesis, SGM-3 beamline of ASTRID2 for ARPES measurements, QUANTUMESPRESSO suite for DFT calculations.

4：Experimental Procedures and Operational Workflow:

Single-layer MoS2 was grown on Au(111), characterized by ARPES, and the temperature-dependent linewidths of the spin–split bands were measured and analyzed.

5：Data Analysis Methods:

The temperature-dependent linewidths were fitted using a Debye model to extract the electron–phonon coupling parameter λ. DFT calculations were performed to compare with experimental results.