FERUGLIO, ChiaraChiaraFERUGLIOMAIO, UmbertoUmbertoMAIOTRIPODI, RobertaRobertaTRIPODIWinters, Jan MartinJan MartinWintersZAPPACOSTA, LucaLucaZAPPACOSTABISCHETTI, ManuelaManuelaBISCHETTICivano, FrancescaFrancescaCivanoCarniani, StefanoStefanoCarnianiD'ODORICO, ValentinaValentinaD'ODORICOFIORE, FabrizioFabrizioFIOREGallerani, SimonaSimonaGalleraniGINOLFI, MICHELEMICHELEGINOLFIMaiolino, RobertoRobertoMaiolinoPICONCELLI, EnricoEnricoPICONCELLIVALIANTE, RosaRosaVALIANTEZANCHETTIN, Maria VittoriaMaria VittoriaZANCHETTIN2024-12-062024-12-0620232041-8205http://hdl.handle.net/20.500.12386/35410We report the detection of CO(6-5) and CO(7-6) and their underlying continua from the host galaxy of quasar J100758.264+211529.207 (Pōniuā‘ena) at z = 7.5149, obtained with the NOrthern Extended Millimeter Array. Pōniuā‘ena belongs to the HYPerluminous quasars at the Epoch of ReionizatION sample of 18 z > 6 quasars selected to be powered by supermassive black holes, which experienced the fastest mass growth in the first cosmic gigayear. The one reported here is the highest-redshift measurement of the cold and dense molecular gas to date. The host galaxy is unresolved, and the line luminosity implies a molecular reservoir of M(H2) = (2.2 ± 0.2) × 1010 M ⊙, assuming a CO spectral line energy distribution typical of high-redshift quasars and a conversion factor α = 0.8 M ⊙ ( K km s − 1 pc 2 ) − 1 . We model the cold dust spectral energy distribution to derive a dust mass of M dust = (1.7 ± 0.6) × 108 M ⊙ and thus, a gas-to-dust ratio ∼130. Both the gas and dust mass are remarkably similar to the reservoirs found for luminous quasars at z ∼ 6-7. We use the CO detection to derive an estimate of the cosmic mass density of H2, Ω H 2 ≃ 1.31 × 10 − 5 . This value is in line with the general trend suggested by literature estimates at z < 7 and agrees fairly well with the latest theoretical expectations of nonequilibrium molecular-chemistry cosmological simulations of cold gas at early times.STAMPAenArticle10.3847/2041-8213/ace0c82-s2.0-85170046514https://iopscience.iop.org/article/10.3847/2041-8213/ace0c8https://api.elsevier.com/content/abstract/scopus_id/85170046514FIS/05 - ASTRONOMIA E ASTROFISICA