J/A+A/550/A18ivo://CDS.VizieR/J/A+A/550/A18doi:10.26093/cds/vizier.35500018CDSNucita A.A.Manni L.De Paolis F.Vetrugno D.Ingrosso G.2017-09-19T14:20:51Z2013-05-27T11:25:51ZCDS support team

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

cds-question@unistra.frgalaxiesx-ray-sourcesWe report the results of a deep archive XMM-Newton observation of the Fornax spheroidal galaxy that we analyzed with the aim of fully characterizing the X-ray source population (in most of the cases likely to be background active galactic nuclei) detected towards the target. A cross correlation with the available databases allowed us to find a source that may be associated with a variable star belonging to the galaxy. We also searched for X-ray sources in the vicinity of the Fornax globular clusters GC 3 and GC 4 and found two sources probably associated with the respective clusters. The deep X-ray observation was also suitable for the search of the intermediate-mass black hole (of mass~=10^4^M_{sun}_) expected to be hosted in the center of the galaxy. In the case of Fornax, this search is extremely difficult since the galaxy centroid of gravity is poorly constrained because of the large asymmetry observed in the optical surface brightness. Since we cannot firmly establish the existence of an X-ray counterpart of the putative black hole, we put constraints only on the accretion parameters. In particular, we found that the corresponding upper limit on the accretion efficiency, with respect to the Eddington luminosity, is as low as a few 10^-5^.2013A&A...550A..18Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/550/A18CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/xmm : XMM-Newton Observation Log (XMM-Newton SOC, 2013)I/284 : The USNO-B1.0 Catalog (Monet+ 2003)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)J/A+A/544/A73 : BVI photometry of Fornax dSph galaxy (de Boer+, 2012)J/AJ/131/912 : BR photometry of Fornax dSph center (Olszewski+, 2006)J/AJ/131/2114 : Radial velocities in Fornax dSph (Walker+, 2006)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/550/A18https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/550/A18http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/550/A18https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/550/A18https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/550/A18http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/550/A18GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/550/A18/table1 (The X-ray sources detected by our analysis towards the Fornax dSph)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/550/A18/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/550/A18/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/550/A18/table1?GETtext/xml+votable180.050000true40.211667-34.4569170.005555555555555556Cone search capability for table J/A+A/550/A18/table2 (List of the detected X-ray sources cross-correlated with the catalog GMD093 (Gizis et al., 1993PASP..105..871G))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/550/A18/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/550/A18/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/550/A18/table2?GETtext/xml+votable180.050000true40.065417-34.2230830.0055555555555555566/35883 35968-359698.650015785639275e-20 1.7003137259100215e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/550/A18?format=asciiX-raydefaultJ/A+A/550/A18/table1The X-ray sources detected by our analysis towards the Fornax dSphrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMSimbad column added by the CDSmeta.ref.urlcharSrc[1/107] Source numbermeta.id;meta.mainintprimaryn_Src[*VM ] Notes on source (1)meta.notecharN[A-G] Label indicating which EPIC camera(s) identified the source (2)meta.id;instrcharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainePosError on positionarcsecstat.error;posfloatHR1Hardness ratio 1, HR1=(H-M)/(S+M+H) (3)phot.flux;arith.ratiofloate_HR1rms uncertainty on HR1stat.errorfloatHR2Hardness ratio 2, HR1=(M-S)/(S+M+H) (3)phot.flux;arith.ratiofloate_HR2rms uncertainty on HR2stat.errorfloatFXMinimum absorbed flux in 0.2-12keV band1e-17W.m**-2phot.flux;em.X-rayfloate_FXrms uncertainty on FX1e-17W.m**-2stat.errorfloatr2M? Distance to 2MASS source (Cat. II/246)arcsecpos.angDistancefloatnullablerUB? Distance to USNO-B1 source (Cat. I/284)arcsecpos.angDistancefloatnullableJ/A+A/550/A18/table2List of the detected X-ray sources cross-correlated with the catalog GMD093 (Gizis et al., 1993PASP..105..871G)RefReferences (2)meta.refcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[GMD93][1/19] Gizis et al. number (1993PASP..105..871G) (1)meta.id;meta.mainintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainSrc[1/107]? X-ray Src number (1)meta.idintnullableDist? Distance between [GMD93] and Src sourcesarcsecpos.angDistanceintnullablee_Dist? rms uncertainty on Distarcsecstat.errorintnullableTypeMorphological typesrc.morph.typecharJ/A+A/550/A18/table3*A few sources of the X-ray sample detected towards the Fornax dSph correlated with the 2MASS catalogSrc[1/107]Src numbermeta.id;meta.mainintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFXX-ray flux in 0.2-2.4keV band1e-17W.m**-2phot.flux;em.X-rayfloate_FXrms uncertainty on FX1e-17W.m**-2stat.errorfloatFJ2MASS J-band flux1e-16W.m**-2phot.flux;em.IR.Jfloate_FJrms uncertainty on FJ1e-16W.m**-2stat.errorfloatJmag2MASS J magnitudemagphot.mag;em.IR.Jfloate_Jmagrms uncertainty on Jmagmagstat.error;phot.mag;em.IR.JfloatKmag2MASS Ks magnitudemagphot.mag;em.IR.Kfloate_Kmagrms uncertainty on Kmagmagstat.error;phot.mag;em.IR.Kfloat