J/A+A/706/A136ivo://CDS.VizieR/J/A+A/706/A136CDSMercier W.Kalita B.S.Shuntov M.Arango-Toro R.C.Ilbert O.Tresse L.,Dubois Y.Laigle C.Hatamnia H.McMahon N.Faisst A.L.Cox I.G.,Trebitsch M.Michel-Dansac L.Yu S.-YHirschmann M.Huertas-Company M.,Long A.S.Koekemoer A.M.Aufort G.Lewis J.S.W.Gozaliasl G.Rich R.M.,Rhodes J.McCracken H.J.Casey C.M.Kartaltepe J.S.Robertson B.E.,Franco M.Liu D.Akins H.B.Allen N.Toft S.2026-03-02T06:25:50Z2026-02-05T08:55:50ZCDS support team

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

cds-question@unistra.frgalaxiescatalogsgalaxy-classification-systemsinfrared-astronomyClumps in the rest-frame UV emission of galaxies at z<3 have been observed for decades. Since the launch of the James Webb Space Telescope (JWST), a large population is detected in the rest-frame near-infrared (NIR), raising questions about their formation mechanism. We investigate the presence and properties of NIR overdensities (hereafter substructures, including clumps) in star-forming and quiescent galaxies at 1<z<4 to understand their link to the evolution of their host galaxy. Methods: We identify substructures in JWST/NIRCam F277W and F444W residual images at a rest-frame wavelength of 1um. The fraction of galaxies with substructures with M*>10^9^M_{sun}_ has steadily decreased with cosmic time from 40% at z=4 to 10% at z=1. NIR clumps, the most common type of small substructures, are much fainter (2% of the total galaxy flux) than similar UV clumps in the literature. Nearly all galaxies at the high-mass end of the main sequence (MS), starburst, and green valley regions have substructures. However, we do not find substructures in low-mass galaxies in the green valley and red sequence. Although massive galaxies on the MS and in the green valley have a 40% probability of hosting multiple clumps, the majority of clumpy galaxies host only a single clump. Conclusions: The fraction of clumpy galaxies in the rest-frame NIR is determined by the stellar mass and SFR of the host galaxies. Its evolution with redshift is due to galaxies moving toward lower SFRs at z<2 and the build-up of low-mass galaxies in the green valley and red sequence. Based on their spatial distribution in edge-on galaxies, we infer that most of substructures are produced in-situ via disk fragmentation. Galaxy mergers may still play a role at high stellar masses, especially at low SFR.2026A&A...706A.136Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/706/A136CatalogResearchIsServedByTAP 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/706/A136https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/706/A136http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/706/A136https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/706/A136https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/706/A136http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/706/A136GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/706/A136/detec (Catalogue containing the substructure detections and their properties)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/706/A136/detec?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/706/A136/detec?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/706/A136/detec?GETtext/xml+votable180.050000true149.75346866433432.13825187201620.0055555555555555565/6814 6/https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/706/A136?format=asciiOpticalInfrareddefaultJ/A+A/706/A136/sample*Catalogue containing the selected of galaxies with M*>10^9^M_{sun}_ at 1<z<4recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDetecindicates substructures in detec.dat filemeta.ref.urlcharIDSE++Unique identifier used to match the galaxies to the COSMOS2025 catalogue of Shuntov et al. (2025A&A...704A.339S, Cat. J/A+A/704/A339, arXiv:2506.03243)meta.id;meta.mainintprimarypSint=1Probability that galaxies host exactly one substructure of any size detected with the intrinsic approachstat.fit.goodnessdoublepCint=1Probability that galaxies host exactly one clump detected with the intrinsic approachstat.fit.goodnessdoublepMint=1Probability that galaxies host exactly one moderately large substructure detected with the intrinsic approachstat.fit.goodnessdoublepLint=1Probability that galaxies host exactly one extended substructure detected with the intrinsic approachstat.fit.goodnessdoublepSopt=1Probability that galaxies host exactly one substructure of any size detected with the optimal approachstat.fit.goodnessdoublepCopt=1Probability that galaxies host exactly one clump detected with the optimal approachstat.fit.goodnessdoublepMopt=1Probability that galaxies host exactly one moderately large substructure detected with the optimal approachstat.fit.goodnessdoublepLopt=1Probability that galaxies host exactly one extended substructure detected with the optimal approachstat.fit.goodnessdoublepSint>=1Probability that galaxies host one or more substructures of any size detected with the intrinsic approachstat.fit.goodnessdoublepCint>=1Probability that galaxies host one or more clumps detected with the intrinsic approachstat.fit.goodnessdoublepMint>=1Probability that galaxies host one or more moderately large substructures detected with the intrinsic approachstat.fit.goodnessdoublepLint>=1Probability that galaxies host one or more extended substructures detected with the intrinsic approachstat.fit.goodnessdoublepSopt>=1Probability that galaxies host one or more substructures of any size detected with the optimal approachstat.fit.goodnessdoublepCopt>=1Probability that galaxies host one or more clumps detected with the optimal approachstat.fit.goodnessdoublepMopt>=1Probability that galaxies host one or more moderately large substructures detected with the optimal approachstat.fit.goodnessdoublepLopt>=1Probability that galaxies host one or more extended substructures detected with the optimal approachstat.fit.goodnessdoublepSint>=2Probability that galaxies host two or more substructures of any size detected with the intrinsic approachstat.fit.goodnessdoublepCint>=2Probability that galaxies host two or more clumps detected with the intrinsic approachstat.fit.goodnessdoublepMint>=2Probability that galaxies host two or more moderately large substructures detected with the intrinsic approachstat.fit.goodnessdoublepLint>=2Probability that galaxies host two or more extended substructures detected with the intrinsic approachstat.fit.goodnessdoublepSopt>=2Probability that galaxies host two or more substructures of any size detected with the optimal approachstat.fit.goodnessdoublepCopt>=2Probability that galaxies host two or more clumps detected with the optimal approachstat.fit.goodnessdoublepMopt>=2Probability that galaxies host two or more moderately large substructures detected with the optimal approachstat.fit.goodnessdoublepLopt>=2Probability that galaxies host two or more extended substructures detected with the optimal approachstat.fit.goodnessdoubleJ/A+A/706/A136/detecCatalogue containing the substructure detections and their propertiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDSE++Unique identifier used to match the galaxies to the COSMOS2025 catalogue of Shuntov et al. (2025A&A...704A.339S, Cat. J/A+A/704/A339, arXiv:2506.03243)meta.id;meta.mainintIDsub[1/38] Unique identifier for each detected substructure (1)meta.idintintrinsicsub[0/1] Whether the substructure is detected with the intrinsic or optimal approachesmeta.codeintRAJ2000Right ascension (J2000) of the pixel with the highest flux associated to the substructuredegpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000) of the pixel with the highest flux associated to the substructuredegpos.eq.dec;meta.mainindexedFluxIntegrated flux of the substructureMJy/srphot.flux.density;em.IRdoubleAreaTotal solid angle area of the substructurearcsec**2pos.posAngdoubleProbProbability that the given substructure belongs to its host galaxystat.probabilitydoubleAreakpc2Total physical area of the substructurekpc**2phys.angSizedouble