J/A+A/675/A143ivo://CDS.VizieR/J/A+A/675/A143doi:10.26093/cds/vizier.36750143CDSComeron S.Trujillo I.Cappellari M.Buitrago F.Garduno L.E.,Zaragoza-Cardiel J.Zinchenko I.A.Lara-Lopez M.A.Ferre-Mateu A.,Dib S.2024-11-28T20:04:07Z2023-07-11T06:16:04ZCDS support team

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

cds-question@unistra.frgalaxiesvisible-astronomyspectroscopyastronomical-modelsAccording to the Lambda cold dark matter cosmology (Lambda-CDM), present-day galaxies with stellar masses Mstar>10^11^M_{sun}_ should contain a sizable fraction of dark matter within their stellar body. Models indicate that in massive early-type galaxies (ETGs) with Mstar~1.5x10^11^M_{sun}_, dark matter should account for ~15% of the dynamical mass within one effective radius (1Re) and for ~60% within 5Re. Most massive ETGs have been shaped through a two-phase process: the rapid growth of a compact core was followed by the accretion of an extended envelope through mergers. The exceedingly rare galaxies that have avoided the second phase, the so-called relic galaxies, are thought to be the frozen remains of the massive ETG population at z>2. The best relic galaxy candidate discovered to date is NGC 1277, in the Perseus cluster. We used deep integral field George and Cynthia Mitchel Spectrograph (GCMS) data to revisit NGC 1277 out to an unprecedented radius of 6kpc (corresponding to 5Re). By using Jeans anisotropic modelling, we find a negligible dark matter fraction within 5Re (fDM(5Re)<0.05; two-sigma confidence level), which is in tension with the Lambda-CDM expectation. Since the lack of an extended envelope would reduce dynamical friction and prevent the accretion of an envelope, we propose that NGC 1277 lost its dark matter very early or that it was dark matter deficient ab initio. We discuss our discovery in the framework of recent proposals, suggesting that some relic galaxies may result from dark matter stripping as they fell in and interacted within galaxy clusters. Alternatively, NGC 1277 might have been born in a high-velocity collision of gas-rich proto-galactic fragments, where dark matter left behind a disc of dissipative baryons. We speculate that the relative velocities of ~2000km/s required for the latter process to happen were possible in the progenitors of the present-day rich galaxy clusters.2023A&A...675A.143Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/675/A143CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/675/A143https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/675/A143http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/675/A143https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/675/A143https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/675/A143http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/675/A143GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/A+A/675/A143/ngc1277Table required to reconstruct the kinematic maps of NGC 1277recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintxX coordinate of the centre of the fibre with respect to the centre of the galaxyarcsecpos.cartesian.x;instr.detfloatyY coordinate of the centre of the fibre with respect to the centre of the galaxyarcsecpos.cartesian.y;instr.detfloatVVelocity corrected for a peculiar velocity of 5097km/s for NGC1277 and 6072km/s for NGC1278km/sphys.velocfloate_VError in the velocitykm/sstat.error;pos.cartesian.yfloatSigmaVelocity dispersionkm/sphys.veloc.dispersionfloate_SigmaError in the velocity dispersionkm/sstat.errorfloatJ/A+A/675/A143/ngc1278Table required to reconstruct the kinematic maps of NGC 1278recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintxX coordinate of the centre of the fibre with respect to the centre of the galaxyarcsecpos.cartesian.x;instr.detfloatyY coordinate of the centre of the fibre with respect to the centre of the galaxyarcsecpos.cartesian.y;instr.detfloatVVelocity corrected for a peculiar velocity of 5097km/s for NGC1277 and 6072km/s for NGC1278km/sphys.velocfloate_VError in the velocitykm/sstat.error;pos.cartesian.yfloatSigmaVelocity dispersionkm/sphys.veloc.dispersionfloate_SigmaError in the velocity dispersionkm/sstat.errorfloatJ/A+A/675/A143/listInformation of spectra.fits filerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintObs.dateObservation datestime.epoch;obsnullableblambdaLower value of wavelength interval0.1nmem.wlfloatBlambdaUpper value of wavelength interval0.1nmem.wlfloatdlambdaWavelenght resolution0.1nmpos.angResolutiondoublesizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar