J/A+A/693/A55ivo://CDS.VizieR/J/A+A/693/A55doi:10.26093/cds/vizier.36930055CDSLyskova N.Churazov E.Khabibullin I.Bikmaev I.F.Burenin R.A.,Forman W.R.Khamitov I.M.Rajpurohit K.Sunyaev R.Jones C.Kraft R.,Zaznobin I.Gorbachev M.A.Suslikov M.V.Gumerov R.I.Sakhibullin N.A.2025-03-07T20:01:09Z2025-01-03T13:59:52ZCDS support team

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

cds-question@unistra.frgalaxy-clustersredshiftedvisible-astronomyMassive clusters of galaxies are very rare in the observable Universe. Mergers of such clusters observed close to pericenter passage are even rarer. Here, we report on one such case: The massive (~10^15^,M_{sun}_ and hot (kT~10keV) cluster CL0238.3+2005 at z=0.42. For this cluster, we combined X-ray data from SRG/eROSITA and Chandra, optical images from DESI, and spectroscopy from the BTA and RTT-150 telescopes. The X-ray and optical morphologies suggest an ongoing merger with a projected separation of the subhalos of ~200kpc. The line-of-sight velocity of galaxies that are tentatively associated with the two merging halos differs by 2000-3000km/s. We conclude that the merger axis is most likely neither close to the line of sight nor to the sky plane. We compare CL0238 with the two well-known clusters MACS0416 and the Bullet and conclude that CL0238 corresponds to an intermediate phase between the pre-merging MACS0416 cluster and the post-merger Bullet cluster. Namely, this cluster recently (only ~=0.1Gyr ago) experienced an almost head-on merger. We argue that this "just after" system is a very rare case and an excellent target for lensing, the Sunyaev-Zeldovich effect, and X-ray studies that can constrain properties ranging from dynamics of mergers to self-interacting dark matter, and plasma effects in the intracluster medium that are associated with shock waves, for instance, electron-ion equilibration efficiency and relativistic particle acceleration.2025A&A...693A..55Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/693/A55CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/693/A55https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/693/A55http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/693/A55https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/693/A55https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/693/A55http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/693/A55GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/693/A55/table1 (Spectroscopic redshifts of individual galaxies in CL0238.3+2005)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/693/A55/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/693/A55/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/693/A55/table1?GETtext/xml+votable180.050000true39.586220.10520.005555555555555556Cone search capability for table J/A+A/693/A55/list (Informations on fits image)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/693/A55/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/693/A55/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/693/A55/list?GETtext/xml+votable180.050000true39.5977520.095420.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/693/A556/624https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/693/A55?format=asciiOpticaldefaultJ/A+A/693/A55/table1Spectroscopic redshifts of individual galaxies in CL0238.3+2005zGalaxy redshiftsrc.redshiftfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension (J2000)degpos.eq.ra;meta.mainDEJ2000Declination (J2000)degpos.eq.dec;meta.maine_zRedshift uncertaintystat.error;src.redshiftfloatVlosGalaxy line-of-sight velocity with respect to the mean cluster redshift <z>=0.4191km/sphys.velocinte_VlosUncertainty on line-of-sight velocitykm/sstat.errorintTelOptical telescope (BTA or RTT-150)instr.telcharJ/A+A/693/A55/listInformations on fits imagerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right Ascension of center (J2000)degpos.eq.ra;meta.mainDEJ2000Declination of center (J2000)degpos.eq.dec;meta.mainscaleScale of the imagearcsec/pixinstr.scalefloatNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintObs.dateObservation datestime.epoch;obsnullablesizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitscharAssocDataAssociated Data web pagemeta.ref.urlchar