J/ApJ/445/280ivo://CDS.VizieR/J/ApJ/445/280doi:10.26093/cds/vizier.14450280CDSGagne M.Caillault J.-P.Stauffer J.R.1999-02-27T11:56:52Z1999-02-27T12:56:42ZCDS support team

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

cds-question@unistra.frx-ray-sourcesnebulaeWe present results from three deep ROSAT high-resolution imager observations of the Orion Nebula star-forming region. The X-ray images contain over 1500 catalogued stars in a roughly 0.8deg^2^ region centered on the Trapezium. In all, 389 distinct X-ray sources have been detected, at least two-thirds of which are associated with a single proper-motion cluster member. X-ray emission is detected from stars of all spectral types, from the massive O- and B-type components of the Trapezium to the coolest, low-mass pre-main-sequence (PMS) stars. In this paper, we focus primarily on X-ray emission from the late-type PMS stars. Of the ~100 late-type cluster members with measured spectral types, approximately three-fourths have been detected; we have derived X-ray luminosity upper limits for the remaining stars. We found coronal X-ray emission turns on around spectral type F6, with the upper envelope of activity increasing with decreasing effective temperature.1995ApJ...445..280Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/445/280CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/171 : Parenago catalogue in the area of the Orion nebula (1954)II/36 : UBV & uvby-beta obs. of Orion OB1 Association (Warren+ 1977)J/ApJ/437/361 : Einstein survey of the Orion nebula region (Gagne+ 1994)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/445/280https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/445/280http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/445/280https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/445/280https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/445/280http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/445/280GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/445/280/table2 (Orion Nebula X-ray sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/445/280/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/445/280/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/445/280/table2?GETtext/xml+votable180.050000true83.503333-4.7397220.005555555555555556ROSAThttps://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/445/280?format=asciiX-raydefaultJ/ApJ/445/280/table2Orion Nebula X-ray sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNoX[1/389]+ X-ray numbermeta.id;meta.mainintprimaryindexedRAJ2000Right ascension J2000pos.eq.ra;meta.mainDEJ2000Declination J2000pos.eq.dec;meta.mainCountCorrected ROSAT HRI count ratect/sphot.count;em.X-raydoublee_Countrms uncertainty on Countct/sstat.errordoubleMult[*] * indicates multiple candidate optical counterparts. See table3meta.notecharParParenago (1954) optical counterpart candidate designationmeta.idcharJ&WJones & Walker (1988) optical counterpart candidate designationmeta.idcharVarVariable optical counterpart candidate designationmeta.idcharProb? Membership probabilitystat.fit.goodnessintnullableDRA? Offset in right ascensionarcsecpos.eq.ra;arith.diffintnullableDDE? Offset in declinationarcsecpos.eq.dec;arith.diffintnullableJ/ApJ/445/280/table3X-ray sources with multiple candidate optical counterpartsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNoX[1/389]+ X-ray numbermeta.id;meta.mainintprimaryindexedPar1Parenago designation of the first candidatemeta.idcharJ&W1Jones & Walker (1988) name of the first candidatemeta.idcharProb1? Membership probability of the first candidatestat.fit.goodnessintnullableDRA1Offset in right ascension of the first candidatearcsecpos.eq.ra;arith.diffintDDE1Offset in declination of the first candidatearcsecpos.eq.dec;arith.diffintPar2Parenago designation of the second candidatemeta.idcharJ&W2Jones & Walker (1988) name of the second candidatemeta.idcharProb2? Membership probability of the second candidatestat.fit.goodnessintnullableDRA2Offset in right ascension of the second candidatearcsecpos.eq.ra;arith.diffintDDE2Offset in declination of the second candidatearcsecpos.eq.dec;arith.diffintPar3Parenago designation of the third third candidatemeta.idcharJ&W3Jones & Walker (1988) name of the third candidatemeta.idcharProb3? Membership probability of the third candidatestat.fit.goodnessintnullableDRA3? Offset in right ascension of the third candidatearcsecpos.eq.ra;arith.diffintnullableDDE3? Offset in declination of the first candidatearcsecpos.eq.dec;arith.diffintnullableJ/ApJ/445/280/table6Optical and X-ray data for Group 1 starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharNoX[1/389]? X-ray numbermeta.idintnullableSpSpectral typesrc.spTypecharlogTeff? Effective temperaturelog(K)phys.temperature.effectivefloatnullableu_logTeffUncertainty flag on logTeffmeta.code.errorcharBmag? B magnitudemagphot.mag;em.opt.BfloatnullableVmag? V magnitudemagphot.mag;em.opt.VfloatnullableIcmag? Ic (Cousins system) magnitudemagphot.mag;em.opt.IfloatnullableAVVisual extinction (1)magphys.absorptionfloatn_AV[)] ')' when AV=0.25mag (1)meta.notecharl_vsiniLimit flag on vsinimeta.code.errorcharvsini? Spectroscopic rotation velocitykm/sphys.veloc.rotatintnullableProt? Rotational perioddtime.periodfloatnullablel_logLXLimit flag on logLXmeta.code.errorcharlogLXX-ray luminositylog(1e-07J)phys.luminosity;em.X-rayfloatl_logLX/LbolLimit flag on logLX/Lbolmeta.code.errorcharlogLX/Lbol? X-ray luminosity versus bolometric luminosityphys.luminosity;arith.ratiofloatnullableu_logLX/LbolUncertainty flag on logLX/Lbolmeta.code.errorcharNoteNotes (2)meta.notechar