J/A+A/713/A105ivo://CDS.VizieR/J/A+A/713/A105CDSMotte F.Le Nestour N.Veyry R.Brouillet N.Nony T.Thomasson B.,Louvet F.Joncour I.Moraux E.Men'shchikov A.Yoo T.Ginsburg A.,Gusdorf A.Stutz A.M.Galvan-Madrid R.Csengeri T.,Alvarez-Gutierrez R.H.Armante M.Bernard Y.Bonfand M.Chevalier S.,Cunningham N.Dell'Ova P.Gonzalez M.Koley A.Olguin F.A.Panda D.,Pouteau Y.Salinas J.Sanhueza P.Sandoval-Garrido N.A.,Valeille-Manet M.2026-09-15T17:42:04Z2026-09-15T18:41:34ZCDS support team

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

cds-question@unistra.frmolecular-cloudsradio-sourcesgalaxy-classification-systemsThe gravoturbulent fragmentation of the interstellar medium is expected to create a hierarchical cascade of cloud structures, crossing the scales from core to disk. We aim to predict how the currently observed top-heavy core mass function (CMF) in the massive protocluster W43-MM1 evolves due to core subfragmentation. We used the getsf algorithm to extract sources in five ALMA images of W43-MM1 at 3mm, with a spatial resolution ranging from 14kau to 270au. Then, we applied FAMILY, a graph-theory-based analysis tool, to create and characterize networks of nested sources in W43-MM1. We compared the hierarchical fragmentation cascade of W43-MM1 to those measured in the NGC 2264 protocluster and in synthetic images of an Orion-like protocluster simulated by magneto-hydrodynamical calculations. Assuming self-similarity, we measured a small fractality index of F3D=1.19+/-0.10 in W43-MM1, which means that, on average, a cloud structure fragments into only 1.19 fragments each time the physical scale decreases by a factor of two. In line with values measured above the core scale in the NGC 2264 and synthetic protoclusters, the W43-MM1 fractality index increases by about 30% at larger scales. We also estimate an imbalanced mass partition between siblings, with two-thirds of the mass of siblings at a given scale belonging to the dominant sibling. The mass transfer efficiency, computed from one physical scale to another, is high and corresponds to a core formation efficiency (CFE) from 2400 au cores to 200au seeds of ~16%. Based on the fractality and efficiency values measured in W43-MM1, the gravoturbulent model by Thomasson predicts that its fragmentation below ~14kau is not driven by turbulence but by gravity. Using these parameters and the measured mass partition, we demonstrate that the seed mass function, from which the initial mass function (IMF) emerges, has a high-mass end that remains top-heavy. Therefore, based on our current assumptions, core subfragmentation in W43-MM1, and perhaps more broadly in massive Galactic protoclusters, plays a minimal role in shaping the high-mass slope of the IMF.2026A&A...713A.105Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/713/A105CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/542/A76 : Herschel-HIFI water spectra of W43-MM1 (Herpin+, 2012)J/A+A/636/A38 : W43-MM1 ALMA ^12^CO(2-1) datacube (Nony+, 2020)J/A+A/674/A75 : W43-MM1 and W43-MM2+MM3 ALMA datacubes (Nony+, 2023)J/other/NatAs/2.478 : Cores detected at 1.3mm in W43-MM1 (Motte+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/713/A105https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/713/A105http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/713/A105https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/713/A105https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/713/A105http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/713/A105GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/713/A105/tableb1 (ALMA 3mm sources found in the W43-MM1 protocluster)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/713/A105/tableb1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/713/A105/tableb1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/713/A105/tableb1?GETtext/xml+votable180.050000true281.9451667-1.90814720.0055555555555555566/30262https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/713/A105?format=asciiOpticalRadiodefaultJ/A+A/713/A105/tableb1ALMA 3mm sources found in the W43-MM1 protoclusterRAJ2000Right ascension (J2000)pos.eq.ra;meta.maine_SPeak3mmError on the peak fluxmJy/beamstat.errorfloatSInt3mmIntegrated flux at a given central frequency (2)mJyphot.flux.density;em.mm.50-100GHzfloate_SInt3mmError on the integrated fluxmJystat.errorfloatFamilyTreeAscending nodes of the source family treestat.fit.paramchargetsfNoImage number followed by getsf source number (N_NN) (1)meta.idcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNodeNo[0/191] Source number in the hierarchical network (nodes) (1)meta.id;meta.mainintDEJ2000Declination (J2000)pos.eq.dec;meta.mainMajAxis3mmMajor size at half maximumarcsecphys.angSizefloatMinAxis3mmMinor size at half maximumarcsecphys.angSize.sminAxisfloatPAParallactic angle (counterclockwise ellipse orientation from north to east)degpos.posAngintSPeak3mmPeak flux at given central frequency and beam size (2)mJy/beamphot.flux.density;em.mm.50-100GHzfloat