J/A+A/344/521ivo://CDS.VizieR/J/A+A/344/521doi:10.26093/cds/vizier.33440521CDSHaberl F.Pietsch W.2003-01-12T21:00:28Z2003-01-12T22:00:20ZCDS support team

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

cds-question@unistra.frx-ray-sourcesmagellanic-cloudsThe ROSAT PSPC (Cat. <IX/11>) performed more than 200 pointed observations of the Large Magellanic Cloud (LMC) between 1990 and 1994. Most of the LMC was covered more than once and a large fraction at least ten times, making the PSPC observations an in valuable archive to study long-term time variability in the LMC. We performed a systematic search for variable X-ray sources in the LMC and found 27 sources which showed flux variations by factors between 3 and more than 1000. A comparison of the temporal and spectral characteristics of 15 X-ray sources which are not yet identified optically with those of the previously known sources in our sample allows to draw first conclusions about their nature. Up to six of the unidentified sources are promising candidates for high mass X-ray binaries in the LMC. Six sources are probably foreground stars, two soft objects might be supersoft sources and one source could be a black hole candidate. Most of the X-ray binary candidates are found in the area of the LMC 4 supergiant shell leading to a significant concentration of such systems in that region, consistent with the idea of being born in the stellar formation event which created the shell.1999A&A...344..521Hhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/344/521CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toIX/11 : ROSAT PSPC Source Catalog (Voges+ 1994)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/344/521https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/344/521http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/344/521https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/344/521https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/344/521http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/344/521GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/344/521/table1 (Variable sources in the LMC region. I.)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/344/521/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/344/521/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/344/521/table1?GETtext/xml+votable180.050000true85.895833-64.3822220.005555555555555556ROSAT6/33055 33079 33090 33096-33098 33103 33107 33112-33113 33116-33117 33121 33124 33126 33795https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/344/521?format=asciiX-raydefaultJ/A+A/344/521/table2Variable sources in the LMC region II.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[HP99]Catalogue entrymeta.id;meta.mainintUl? Lowest upper limit0.01count.s**-1phot.count;em.X-rayfloatnullableMin? Detection minimumct/sphot.count;em.X-rayfloatnullableMax? Detection maximumct/sphot.count;em.X-rayfloatnullableSup? Highest detection influenced by support structure (which gives a lower limit)ct/sphot.count;em.X-rayfloatnullablel_VarLimit flag on Varmeta.code.errorcharVarVariabilitysrc.var.indexfloatn_Var[a] Note on Var (1)meta.notecharl_ProbLimit flag on Probmeta.code.errorcharProb? Probability for variability in {sigma} (not given if higher than 6)stat.fit.goodness;src.varfloatnullableNgNumber of good detections, used for the variability studymeta.numberintNsNumber of detections near WSS, used for the variability studymeta.numberintNuNumber of upper limits, used for the variability studymeta.numberintRemRemarks (2)meta.notecharJ/A+A/344/521/table1Variable sources in the LMC region. I.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[HP99]Catalogue entrymeta.id;meta.mainintprimaryRA2000Right ascension (2000.0)pos.eq.ra;meta.mainDE2000Declination (2000.0)pos.eq.dec;meta.mainNote[a] Note on coordinates and r90 (1)meta.notecharr9090% statistical position uncertainty, the systematic error is ~7"arcsecstat.errorfloatEEnergy band of detection (2)instr.bandpassintCountRateCount rate in broad band Ect/sphot.count;em.X-raydoublee_CountRaterms uncertainty on CountRatect/sstat.errorfloatHR1Hardness ratios HR1=(hard-soft)/(hard+soft)phot.flux;arith.ratiofloate_HR1? rms uncertainty on HR1stat.errorfloatnullablen_HR1[b] Note on HR1 (3)meta.notecharHR2? Hardness ratio HR2=(hard2-hard1)/(hard2+hard1)phot.flux;arith.ratiofloatnullablee_HR2? rms uncertainty on HR2stat.errorfloatnullableOffOff-axis anglearcmininstr.offsetfloatObsROSAT Observation identifiermeta.id;obscharSRateSurvey count rate from Pietsch et al. (1999, in prep.)ct/sphot.count;em.X-raydoublee_SRate? rms uncertainty on SRate (4)ct/sstat.errorfloatnullable