J/A+A/694/A44ivo://CDS.VizieR/J/A+A/694/A44doi:10.26093/cds/vizier.36940044CDSOsinga E.van Weeren R.J.Rudnick L.Andrade-Santos F.Bonafede A.,Clarke T.Duncan K.Giacintucci S.Roettgering H.J.A.2025-03-03T20:02:03Z2025-01-31T10:11:53ZCDS support team

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

cds-question@unistra.frgalaxy-clustersradio-continuum-emissionmagnetic-fieldspolarimetryMagnetic fields remain an elusive part of the content of galaxy clusters. Faraday rotation and depolarisation of extragalactic radio sources are useful probes, but the limited availability of polarised radio sources necessitates the stacking of clusters to study average magnetic field properties. We recently presented a Karl G. Jansky Very Large Array survey of the 124 most massive Planck clusters at low redshift (z<0.35), finding a clear depolarisation trend with the cluster impact parameter, with sources at smaller projected distances to the cluster centre showing more depolarisation. In this study, we combine the depolarisation information with the observed rotation measure (RM) and present an investigation of the average magnetic field properties of the sample, using both background sources and sources embedded in clusters. We observe a significant increase in the RM scatter, {sigma}_RRM_, closer to the cluster centres. Averaging all 124 clusters, we find a scatter within R500 of {sigma}_RRM_=209+/-37rad/m^2^, with background sources and cluster members showing similar values (200+/-33 and 219+/-66rad/m^2^, respectively). In the simple assumption of a uniform amplitude magnetic field with a single fluctuation scale {LAMBDA}c, this translates to an average magnetic field strength of 2({LAMBDA}c/10kpc)^-0.5^uG. The profile of {sigma}_RRM_ as a function of the projected radius is inconsistent with a model that has a simple scaling B{prop.to}n_e_^eta^, with an observed deficit near the centre of clusters possibly caused by the fact that the highest RM sources near the centre of clusters are depolarised. Combining depolarisation and RM in a full forward model, we find that the magnetic field power spectrum roughly agrees with the Kolmogorov value, but that none of the Gaussian random field models can fully explain the observed relatively flat profiles. This implies that more sophisticated models of cluster magnetic fields in a cosmological context are needed.2025A&A...694A..44Ohttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/694/A44CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/694/A44https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/694/A44http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/694/A44https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/694/A44https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/694/A44http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/694/A44GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/694/A44/tablec1 (Polarised source catalogue)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/694/A44/tablec1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/694/A44/tablec1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/694/A44/tablec1?GETtext/xml+votable180.050000true19.55453-27.167670.0055555555555555565/11200 6/87 97 206-207 2388-2389 2488 4206 4965 4976 5099 5438 5524 5597 5701 5712 5931 6011 6014 6017 6019 6088 6090 6867 6873 7026 7242-7243 7513 7768-7769 7928 8220 8520 9036 9050 9072 9157 9168 9354 9366 9468 9476 9486 9504 9506 9508 9593 9997 9999 10306 10312-10313 10315 10318 10379 10527 10664 11042 11063 11080 11219 11222 11253 11467 11613 11626 11809 11811 12072 12253 12255 12640 12642 12653 12664 12732 12734 14879 15112 15192-15193 15286 15351 16030-16034 16229 16609 16700 16702 16713 17237 17239 17456-17457 18016-18017 18019 18566 18578 18584-18585 18683 18800 18894 19089 19091 19101 19103 19451 19935 20302 20873-20874 21763 21766 22577 22580 22607 22786 22792 23451 23454 24822 24943 25188 25300 25302 25391 25402 25542 26080 26135 26186 26189 26208-26209 26299 26302 27136-27137 27417 27420 27595 27598 27660-27661 27668 27742 28181 28249 28251 28427-28430 28619-28620 28622 31536-31537 31851 32500 32602 32693 35765 35950 36017 36434 38853 38858-38859 40809 43948 43950 43977 44820 45044 48735 48964 48966https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/694/A44?format=asciiRadiodefaultJ/A+A/694/A44/tablec1Polarised source catalogueRAJ2000Source right ascension (J2000) (RA)degpos.eq.ra;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintDEJ2000Source declination (J2000) (DEC)degpos.eq.dec;meta.maine_RAJ2000? Source right ascension uncertainty (E_RA)degstat.error;pos.eq.radoublenullablee_DEJ2000? Source declination uncertainty (E_DEC)degstat.error;pos.eq.decdoublenullableMajSource major axis (Maj)arcsecphys.angSizefloatMinSource minor axis (Min)arcsecphys.angSize;srcfloate_Maj? Source major axis uncertainty (E_Maj)arcsecstat.errorfloatnullablee_Min? Source minor axis uncertainty (E_Min)arcsecstat.error;stat.minfloatnullablePA[] Source position angle (PA)degpos.posAngfloate_PA? Source position angle uncertainty (E_PA)degstat.errordoublenullablePFExtDepol? Best fit intrinsic polarisation fraction (PolFrac_ExtDepol)phys.polarization.lineardoublenullablee_PFExtDepol[]? Lower uncertainty on PolFracER (PolFrac_ErrNeg_ExtDepol)stat.errordoublenullableE_PFExtDepol? Upper uncertainty on PolFracER (PolFrac_ErrPos_ExtDepol)stat.error;stat.maxdoublenullableIAExtDepol? Best fit intrinsic polarisation angle (IntrAngl_ExtDepol)radphys.polarizationfloatnullablee_IAExtDepol[]? Lower uncertainty on IAExtDepol (IntrAngl_ErrNeg_ExtDepol)radstat.errorfloatnullableE_IAExtDepol? Upper uncertainty on IAExtDepol (IntrAngl_ErrPos_ExtDepol)radstat.error;stat.maxfloatnullableRMExtDepol? Best fit RM (RM_ExtDepol)rad.m**-2phys.polarization.rotMeasuredoublenullablee_RMExtDepol[]? Lower uncertainty on RMExtDepol (RM_ErrNeg_ExtDepol)rad.m**-2stat.errordoublenullableE_RMExtDepol? Upper uncertainty on RMExtDepol (RM_ErrPos_ExtDepol)rad.m**-2stat.error;stat.maxdoublenullablesigRMExtDepol? Best fit depolarisation (sigmaRM) (sigmaRM_ExtDepol)rad.m**-2phys.polarization.rotMeasuredoublenullablee_sigRMExtDepol[]? Lower uncertainty on sigRMExtDepol (sigmaRM_ErrNeg_ExtDepol)rad.m**-2stat.errordoublenullableE_sigRMExtDepol? Upper uncertainty on sigRMExtDepol (sigmaRM_ErrPos_ExtDepol)rad.m**-2stat.error;stat.maxdoublenullableI0ExtDepol? Best fit I0 (I_0_ExtDepol)mJystat.fit.param;meta.modelledfloatnullablee_I0ExtDepol[]? Lower uncertainty on I0ExtDepol (I_0_ErrNeg_ExtDepol)mJystat.errorfloatnullableE_I0ExtDepol? Upper uncertainty on I0ExtDepol (I_0_ErrPos_ExtDepol)mJystat.error;stat.maxfloatnullableaExtDepol? Best fit spectral index (a_ExtDepol)spect.indexfloatnullablee_aExtDepol[]? Lower uncertainty on aExtDepol (a_ErrNeg_ExtDepol)stat.errorfloatnullableE_aExtDepol? Upper uncertainty on aExtDepol (a_ErrPos_ExtDepol)stat.error;stat.maxfloatnullablechi2QU? Chi2 value for QU fit (chi2_QU)stat.fit.chi2doublenullablebestz? Best-estimate redshift (z) (bestz)src.redshiftdoublenullablee_bestz? Uncertainty on bestz (bestz_err)stat.errordoublenullabler_bestz[0/4]? Source of bestz (bestz_source) (1)meta.ref;pos.frameintnullablernorm? Radius/R500 to cluster centre (rnorm)phys.size.radius;arith.ratiodoublenullablethetapRadius to pointing centre (theta_p)aminphys.angSize;srcdoubleClusterName of target cluster, GLLL.ll+BB.bb (Cluster)meta.id.parentcharRAOdeg? Best estimate optical host right ascension (ra_opthost)degpos.eq.ranullableDEOdeg? Best estimate host declination (dec_opthost)degpos.eq.decnullableMultiFlag[0/1] If Source is multicomponent (MultiCompFlag)meta.codeintFlagged[0/1] If Source was flagged (Flagged)meta.code.errorintNoteAdditional notes (Note)meta.notecharRRM? Best fit RM minus galactic contribution (RRM)rad.m**-2phys.polarization.rotMeasuredoublenullablee_RRM? Lower uncertainty (RRM_ErrNeg)rad.m**-2stat.errordoublenullableE_RRM? Upper uncertainty (RRM_ErrPos)rad.m**-2stat.error;stat.maxdoublenullablebehind[0/1] Source is behind target cluster (behind)meta.codeintinside[0/1] Source is inside target cluster (inside)meta.codeint