J/A+A/712/A16ivo://CDS.VizieR/J/A+A/712/A16CDSMeyer R.A.Wang F.Kakiichi K.Brammer G.Champagne J.Jurk K.Li Z.,Li Z.Musin M.Satyavolu S.Schindler J.-T.Shuntov M.Xu Y.Zou S.,Bian F.Casey C.Egami E.Fan X.Jiang D.Laporte N.Liu W.,Oesch P.A.Tasca L.Yang J.Zhang Z.Akins H.Cai Z.Coulter D.A.,Huang J.Li M.Liu W.Liang Y.Jin B.Jin X.Kartaltepe J.,Koekemoer A.M.Matharu J.Pudoka M.Tee W.-L.Witten C.Zhang H.,Zhu Y.2026-07-30T12:34:39Z2026-07-30T13:34:01ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frgalaxiescatalogsredshiftedspectroscopyinfrared-astronomyWe present a catalogue of spectroscopically-selected [OIII]+Hbeta emitters at 6.75<z<9.05 and the resulting [OIII] 5008{AA} Luminosity Function (LF) in the COSMOS field. We leverage the 0.33deg^2^ covered by COSMOS-3D using NIRCam/WFSS F444W to perform the largest spectroscopic search for [OIII] emitters at 6.75<z<9.05. We present our catalogue of 249 [OIII] emitters and their associated completeness function. The inferred constraints on the [OIII] LF enable us to characterise the knee of the [OIII] 5008{AA} LF, resulting in improved [OIII] 5008{AA} LF constraints at z~7, 8. Notably, we find evidence for a decline of the [OIII] luminosity density between z~6-8, which could be expected if the metallicity of [OIII] emitters, as well as the cosmic star-formation rate density, is declining at these redshifts. We find that theoretical models that reproduce the z~7,8 [OIII] 5008{AA} LF do not reproduce well the [OIII] equivalent width distribution, pointing to potential challenges in the modelling of [OIII] and other nebular lines in the early Universe. Finally, we provide the first constraints on the cosmic variance of [OIII] emitters, estimating at 15% the fractional uncertainty for the z~7,8 [OIII] 5008{AA} LF in the 0.33deg^2^ field. This estimate is in good agreement with that inferred from clustering, and shows that the [OIII] 5008{AA} LF derived from smaller extragalactic legacy fields is strongly affected by cosmic variance. Our results highlight the fundamental role that wide-area JWST slitless surveys play to map the galaxy large-scale structure down into the reionisation era, serving as a springboard for a variety of science cases.2026A&A...712A..16Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/712/A16CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/704/A339 : COSMOS2025 (Shuntov+, 2025)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/712/A16https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/712/A16http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/712/A16https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/712/A16https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/712/A16http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/712/A16GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/712/A16/tableb1 (Catalogue of [O III] emitters presented in this work)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/712/A16/tableb1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/712/A16/tableb1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/712/A16/tableb1?GETtext/xml+votable180.050000true149.8405513564052.114942087352710.0055555555555555566/27256 27258https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/712/A16?format=asciiInfrareddefaultJ/A+A/712/A16/tableb1Catalogue of [O III] emitters presented in this workFO35008Measured [OIII] 5008 flux [erg/s/cm^2]mW.m**-2phot.fluxdoublee_FO35008Uncertainty[OIII] 5008 flux [erg/s/cm^2]mW.m**-2stat.errordoubleF444WmagF444W model magnitude (from Shuntov+2025)magphot.mag;em.opt.B;meta.modelleddoublee_F444WmagF444W model magnitude error (from Shuntov et al., 2025, Cat. J/A+A/704/A339)magstat.errordoubleComplEnd-to-end completeness of emittermeta.notedoublee_ComplCompleteness errorstat.errordoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCWEBCOSMOS-Web ID (Shuntov et al., 2025, Cat. J/A+A/704/A339)meta.id;meta.mainintRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.mainmedGradeMedian grade of Visual Inspectionmeta.code.qualfloatzBest-fit redshiftsrc.redshiftdoubleFHb? Measured H-beta flux [erg/s/cm^2]mW.m**-2phot.flux;spect.linedoublenullablee_FHb? Uncertainty H-beta flux [erg/s/cm^2]mW.m**-2stat.errordoublenullableFO34960Measured [OIII] 4960 flux [erg/s/cm^2]mW.m**-2phot.fluxdoublee_FO34960Uncertainty[OIII] 4960 flux [erg/s/cm^2]mW.m**-2stat.errordouble