M. AckermannM. AjelloA. AlbertW. B. AtwoodL. BaldiniJ. BalletG. BarbielliniD. BastieriR. BellazziniE. BissaldiR. D. BlandfordE. D. BloomR. BoninoE. BottaciniT. J. BrandtJ. BregeonP. BruelR. BuehlerT. H. BurnettR. A. CameronR. CaputoM. CaragiuloP. A. CaraveoE. CavazzutiC. CecchiE. CharlesA. ChekhtmanJ. ChiangA. ChiappoG. ChiaroS. CipriniJ. ConradF. CostanzaA. CuocoS. CutiniF. D'AmmandoF. De PalmaR. DesianteS. W. DigelN. Di LallaM. Di MauroL. Di VenereP. S. DrellC. FavuzziS. J. FeganE. C. FerraraW. B. FockeA. FranckowiakY. FukazawaS. FunkP. FuscoF. GarganoD. GasparriniN. GigliettoF. GiordanoM. GirolettiT. GlanzmanG. A. Gomez-VargasD. GreenI. A. GrenierJ. E. GroveL. GuillemotS. GuiriecM. GustafssonA. K. HardingE. HaysJ. W. HewittD. HoranT. JoglerA. S. JohnsonT. KamaeD. KocevskiM. KussG. La MuraS. LarssonDeutsche Elektronen-SynchrotronClemson UniversityLos Alamos National LaboratorySanta Cruz Institute for Particle PhysicsUniversità di PisaInstitut de Recherche sur les Lois Fondamentales de l'UniversIstituto 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 PisaKavli Institute for Particle Astrophysics and CosmologyUniversità degli Studi di TorinoNASA Goddard Space Flight CenterLaboratoire Univers et Particules de MontpellierLaboratoire Leprince-RinguetUniversity of Washington, SeattleUniversità degli Studi di BariINAF Istituto di Astrofisica Spaziale e Fisica Cosmica, MilanAgenzia Spaziale ItalianaUniversità degli Studi di PerugiaGeorge Mason University, Fairfax CampusStockholms universitetOskar Klein Centre for Cosmoparticle PhysicsRheinisch-Westfälische Technische Hochschule AachenIstituto Di Radioastronomia, BolognaAlma Mater Studiorum Università di BolognaUniversità degli Studi di Napoli Federico IIUniversità degli Studi di UdineHiroshima UniversityErlangen Centre for Astroparticle PhysicsPontificia Universidad Católica de ChileUniversity of MarylandNaval Research LaboratoryUniversite d'OrleansInstitut National des Sciences de l'UniversUniversität GöttingenUniversity of North FloridaFriedrich-Alexander-Universität Erlangen-NürnbergUniversity of TokyoThe Royal Institute of Technology (KTH)Universitat Autònoma de BarcelonaCNRS Centre National de la Recherche ScientifiqueMahidol UniversityUniversity of Denver2018-12-212019-03-142018-12-212019-03-142017-05-01Astrophysical Journal. Vol.840, No.1 (2017)153843570004637X2-s2.0-85019104376https://repository.li.mahidol.ac.th/handle/20.500.14594/42480© 2017. The American Astronomical Society. All rights reserved.. The region around the Galactic Center (GC) is now well established to be brighter at energies of a few GeV than what is expected from conventional models of diffuse gamma-ray emission and catalogs of known gamma-ray sources. We study the GeV excess using 6.5 yr of data from the Fermi Large Area Telescope. We characterize the uncertainty of the GC excess spectrum and morphology due to uncertainties in cosmic-ray source distributions and propagation, uncertainties in the distribution of interstellar gas in the Milky Way, and uncertainties due to a potential contribution from the Fermi bubbles. We also evaluate uncertainties in the excess properties due to resolved point sources of gamma rays. The GC is of particular interest, as it would be expected to have the brightest signal from annihilation of weakly interacting massive dark matter (DM) particles. However, control regions along the Galactic plane, where a DM signal is not expected, show excesses of similar amplitude relative to the local background. Based on the magnitude of the systematic uncertainties, we conservatively report upper limits for the annihilation cross-section as a function of particle mass and annihilation channel.Mahidol UniversityEarth and Planetary SciencesArticleSCOPUS10.3847/1538-4357/aa6cab