Trend of [Eu/Fe] based on the best-fit results of 1D NLTE and LTE. The green squares and blue dots represent the averaged NLTE and LTE [Eu/Fe] ratios across the selected bins. The yellow triangles and cyan circles represent the NLTE and LTE [Eu/Fe] for each stars. The purple dots represent 1D LTE Eu abundance measurements of 1274 metal-rich stars from Gaia-ESO survey. The dashed and solid lines represent the GCE models with different fraction of massive stars that end up with MRSN instead of CCSN.