Level-2 VGK - Product Types - Sentinel-3 Synergy - User Guide
This product is similar to the SY_2_VGP product: same measurement and annotation files, same included parameters. The only difference is that the radiometric measurements have been corrected thanks to the aerosol model computed in SYN Level 2 processing.
There are two additional files, one providing the NDVI the other one the synthetic time associated with each pixel. It has been defined as an internal product, considered as the input of the dedicated VGT-S software.