J/A+A/474/495ivo://CDS.VizieR/J/A+A/474/495doi:10.26093/cds/vizier.34740495CDSAlbacete Colombo J.F.Caramazza M.Flaccomio E.Micela G.Sciortino S.2008-01-28T09:46:35Z2008-01-28T10:45:21ZCDS support team

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

cds-question@unistra.frstellar-associationspre-main-sequence-starsx-ray-sourcesWe characterize individual and ensemble properties of X-ray flares from stars in the Cygnus OB2 and ONC star-forming regions. We analyzed X-ray light-curves of 1003 Cygnus OB2 sources observed with Chandra for 100ks and of 1616 ONC sources detected in the "Chandra Orion Ultra-deep Project" 850ks observation. We employed a binning-free maximum likelihood method to segment the light-curves into intervals of constants signal and identified flares on the basis of both the amplitude and the time-derivative of the source luminosity. We then derived and compared the flare frequency and energy distribution of Cygnus OB2 and ONC sources. The effect of the length of the observation on these results was investigated by repeating the statistical analysis on five 100ks-long segments extracted from the ONC data.2007A&A...474..495Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/474/495CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/AJ/107/1433 : Cygnus OB2 polarimetry (Kobulnicky+, 1994)J/ApJS/149/123 : WSRT survey of Cygnus OB2 (Setia Gunawan+, 2003)J/A+A/464/211 : Chandra and near-IR obs. of Cyg OB2 (Albacete Colombo+, 2007)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/474/495https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/474/495http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/474/495https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/474/495https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/474/495http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/474/495GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/474/495/table1 (X-ray properties of flaring sources in the Cygnus OB2 region.)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/474/495/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/474/495/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/474/495/table1?GETtext/xml+votable180.050000true308.1045416741.172111110.0055555555555555566/14692-14693https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/474/495?format=asciiX-raydefaultJ/A+A/474/495/table1X-ray properties of flaring sources in the Cygnus OB2 region.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordint[AFM2007]Source number according to Albacete Colombo et al. (2007, Cat. <J/A+A/464/211>)meta.id;meta.mainintMass? Mass of star from Albacete Colombo et al. (2007, Cat. <J/A+A/464/211>)solMassphys.massfloatnullablePhotNet detected photon from Albacete Colombo et al. (2007, Cat. <J/A+A/464/211>)ctphot.count;em.X-rayintExMedian photon energy from Albacete Colombo et al. (2007, Cat. <J/A+A/464/211>)keVem.energyfloatlogLXX-ray luminosity from Albacete Colombo et al. (2007, Cat. <J/A+A/464/211>)log(1e-07W)phys.luminosity;em.X-rayfloatlogPKSLogarithm of the KS-test significance (1)stat.fit.goodnessfloatCRCount rate of the characteristic level from MLB analysisct/ksphot.count;em.X-rayfloatTflrFlare duration from MLB analysisstime.scalefloatLXpeakUnabsorbed LX at the flare peak was computed using CF, from MLB analysislog(1e-07W)phys.luminosity;em.X-rayfloatEflrFlare energy from MLB analysiskeVem.energyfloattau.mMeasure of the flare's decay time, Efit/Lmax, from MLB analysishtime.scalefloattau.f? Fitted decay time of flare from MLB analysishtime.scalefloatnullable_RAPosition from Albacete Colombo et al., Cat. J/A+A/464/211 (right ascension part)degpos.eq.ra;meta.main_DEPosition from Albacete Colombo et al., Cat. J/A+A/464/211 (declination part)degpos.eq.dec;meta.main2MASSJName of the 2MASS counterpart (HHMMSSss+DDMMSSs)meta.idchar