We present the First Cosmic Gamma-ray Horizon (1CGH) catalogue, featuring gamma-ray detections above 10GeV based on 16 years of observations with the Fermi Large Area Telescope (LAT) satellite. After carefully selecting a sample of blazars and blazar candidates from catalogues in the literature, we performed a binned likelihood analysis and identified 2791 gamma-ray emitters above 10 GeV, at >3 sigma level, including 62 that are new gamma-ray detections. For each source, we estimated the mean energy of the highest- energy bin and analysed them in the context of the cosmic gamma-ray horizon. By adopting a reference model for the Extragalactic Background Light (EBL), we identified a subsample of 525 sources where moderate to severe gamma-ray absorption could be detected across the redshift range of 0 to 3. This work provides the most up-to-date compilation of detections above 10GeV, along with their redshift information. We condense extensive results from the literature, including reports on observational campaigns dedicated to blazars and gamma-ray sources, thereby delivering an unprecedented review of the redshift information for sources detected above 10GeV. Additionally, we highlight key 1CGH sources where redshift information remains incomplete, offering guidance for future optical observation campaigns. The 1CGH catalogue aims to track the most significant sources for studying the gamma-ray transparency of the universe. Furthermore, it provides a targeted subsample where the EBL optical depth (tau(E,z)) can be robustly measured using Fermi-LAT data.

Cone search capability for table J/MNRAS/539/1458/1cgh_v1 (First Cosmic Gamma-ray Horizon (1CGH) catalogue)