M. AjelloW. B. AtwoodL. BaldiniJ. BalletG. BarbielliniD. BastieriR. BellazziniE. BissaldiR. D. BlandfordE. D. BloomR. BoninoJ. BregeonR. J. BrittoP. BruelR. BuehlerS. BusonR. A. CameronR. CaputoM. CaragiuloP. A. CaraveoE. CavazzutiC. CecchiE. CharlesA. ChekhtmanC. C. CheungG. ChiaroS. CipriniJ. M. CohenD. CostantinF. CostanzaA. CuocoS. CutiniF. D'AmmandoF. De PalmaR. DesianteS. W. DigelN. Di LallaM. Di MauroL. Di VenereA. DomnguezP. S. DrellD. DumoraC. FavuzziS. J. FeganE. C. FerraraP. FortinA. FranckowiakY. FukazawaS. FunkP. FuscoF. GarganoD. GasparriniN. GigliettoP. GiommiF. GiordanoM. GirolettiT. GlanzmanD. GreenI. A. GrenierM. H. GrondinJ. E. GroveL. GuillemotS. GuiriecA. K. HardingE. HaysJ. W. HewittD. HoranG. JóhannessonS. KenseiM. KussG. La MuraS. LarssonL. LatronicoM. Lemoine-GoumardJ. LiF. LongoClemson UniversitySanta Cruz Institute for Particle PhysicsUniversità di PisaUniversite Paris 7- Denis DiderotIstituto Nazionale di Fisica Nucleare, RomaUniversità degli Studi di TriesteIstituto Nazionale Di Fisica Nucleare, Sezione di PadovaUniversità degli Studi di PadovaIstituto Nazionale Di Fisica Nucleare, Sezione di PisaUniversità degli Studi di BariKavli Institute for Particle Astrophysics and CosmologyUniversità degli Studi di TorinoLaboratoire Univers et Particules de MontpellierUniversity of the Free StateLaboratoire Leprince-RinguetDeutsche Elektronen-SynchrotronNASA Goddard Space Flight CenterINAF Istituto di Astrofisica Spaziale e Fisica Cosmica, MilanAgenzia Spaziale ItalianaUniversità degli Studi di PerugiaGeorge Mason University, Fairfax CampusNaval Research LaboratoryUniversity of MarylandRheinisch-Westfälische Technische Hochschule AachenIstituto Di Radioastronomia, BolognaAlma Mater Studiorum Università di BolognaUniversità degli Studi di Napoli Federico IIUniversità degli Studi di UdineUniversidad Complutense de MadridIN2P3 Institut National de Physique Nucleaire et de Physique des ParticulesHarvard-Smithsonian Center for AstrophysicsHiroshima UniversityErlangen Centre for Astroparticle PhysicsUniversite d'OrleansInstitut National des Sciences de l'UniversUniversity of North FloridaUniversity Science Institute ReykjavikNordisk Institut for Teoretisk AtomtysikThe Royal Institute of Technology (KTH)Oskar Klein Centre for Cosmoparticle PhysicsUniversitat Autònoma de BarcelonaStockholms universitetMahidol University2018-12-212019-03-142018-12-212019-03-142017-10-01Astrophysical Journal, Supplement Series. Vol.232, No.2 (2017)006700492-s2.0-85032822161https://repository.li.mahidol.ac.th/handle/20.500.14594/42455© 2017. The American Astronomical Society. All rights reserved.. We present a catalog of sources detected above 10 GeV by the Fermi Large Area Telescope (LAT) in the first 7 years of data using the Pass 8 event-level analysis. This is the Third Catalog of Hard Fermi-LAT Sources (3FHL), containing 1556 objects characterized in the 10 GeV-2 TeV energy range. The sensitivity and angular resolution are improved by factors of 3 and 2 relative to the previous LAT catalog at the same energies (1FHL). The vast majority of detected sources (79%) are associated with extragalactic counterparts at other wavelengths, including 16 sources located at very high redshift (z > 2). Of the sources, 8% have Galactic counterparts and 13% are unassociated (or associated with a source of unknown nature). The high-latitude sky and the Galactic plane are observed with a flux sensitivity of 4.4 to 9.5 ×10-11 ph cm-2 s-1, respectively (this is approximately 0.5% and 1% of the Crab Nebula flux above 10 GeV). The catalog includes 214 new γ-ray sources. The substantial increase in the number of photons (more than 4 times relative to 1FHL and 10 times to 2FHL) also allows us to measure significant spectral curvature for 32 sources and find flux variability for 163 of them. Furthermore, we estimate that for the same flux limit of 10-12 erg cm-2 s-1, the energy range above 10 GeV has twice as many sources as the range above 50 GeV, highlighting the importance, for future Cherenkov telescopes, of lowering the energy threshold as much as possible.Mahidol UniversityEarth and Planetary SciencesArticleSCOPUS10.3847/1538-4365/aa8221