J/A+A/713/A91ivo://CDS.VizieR/J/A+A/713/A91CDSCianfaglione M.De Gasperin F.Cuciti V.Balboni M.van Weeren R.J.,Groeneveld C.Boxelaar J.M.Della Chiesa M.Bonafede A.Di Gennaro G.,Gastaldello F.Brunetti G.2026-09-08T07:12:17Z2026-09-08T08:11:51ZCDS support team

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

cds-question@unistra.frgalaxy-clustersradio-continuum-emissionradio-sourcesinterstellar-mediumIn recent years, clusters have been observed that host multi-component haloes, both in non-merging and merging systems. The existence of these multi-component haloes suggests that there is no clear distinction between the single components. Abell 2244 is an intermediate-mass cluster that hosts a double component diffuse radio emission. The aim of this paper is to carry out an in-depth study of the diffuse radio emission to constrain its origin and characterize its main radio properties. In this work we present LOFAR HBA, MeerKAT UHF, and L-band observations of the cluster Abell 2244. We investigated the nature of the diffuse radio emission, combining high sensitivity radio data with XMM-Newton deep X-ray observations. We also used mock LOFAR observations to investigate contamination of the emission from faint radio sources. We find an integrated spectral index of alpha^1279^_144_=0.9+/-0.1 for both components, where only the radio halo shows spectral steepening at higher frequencies. These values are comparable with the spectral indices observed in disturbed massive clusters. The outer component does not follow the same radio X-ray correlation as the radio halo, which suggests a different physical origin. By analysing the physical and morphological properties of the diffuse emission, we find that the characteristics of the outer component of the emission are intermediate between those of radio haloes and of known megahaloes. Hence, we speculate that the source is either a morphologically disturbed radio halo, caused by a minor merger interaction, or a megahalo but we cannot reach a final classification. From the mock observations, we find that it is unlikely that the emission is caused by faint sources at low resolutions.2026A&A...713A..91Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/713/A91CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/713/A91https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/713/A91http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/713/A91https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/713/A91https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/713/A91http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/713/A91GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/713/A91/list (List of fits images)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/713/A91/list?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/713/A91/list?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/713/A91/list?GETtext/xml+votable180.050000true255.6851134.071620.0055555555555555566/9506https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/713/A91?format=asciiRadiodefaultJ/A+A/713/A91/listList of fits imagesrecnoRecord 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.mainNxNumber of pixels along X-axismeta.numberintNyNumber of pixels along Y-axismeta.numberintObs.dateObservation datestime.epoch;obsnullableFreqobserved frequencyHzem.freqdoublesizeSize of FITS fileKibytephys.size;meta.fitsintFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar