J/A+A/698/A321ivo://CDS.VizieR/J/A+A/698/A321doi:10.26093/cds/vizier.36980321CDSWang X.Takata J.2025-10-10T20:01:18Z2025-06-23T08:05:06ZCDS support team

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

cds-question@unistra.frcataclysmic-variable-starsx-ray-sourcesgamma-ray-astronomyThe cataclysmic variable (CV) is a binary system composed of a white-dwarf (WD) primary and a low-mass main-sequence star. The accretion onto the WD surface causes an X-ray emission, and the CVs are one of the major Galactic X-ray sources. The eROSITA observation offers a new opportunity to identify numerous X-ray-emitting CVs and advance our understanding of its Galactic population. We aim to search for candidates of the X-ray-emitting CVs in the four catalogs of eROSITA, XMM-Newton, Swift, and ROSAT observations. We also intend to examine how the eROSITA survey can enhance the search for new X-ray-emitting CVs. In this study, we identified the candidates of the X-ray-emitting CVs by cross-matching among the four X-ray catalogs and the Gaia sources that are selected from the bridge region between the main sequence and the WD's cooling sequence in the Hertzsprung-Russell diagram. For the selected candidates, we searched for the periodic modulation in the photometry light curves taken by the ZTF and/or TESS observations. The cross-matching selects 444 candidates of the X-ray-emitting CVs, in which 267 sources are the identified CVs. In the other 177 candidates of the X-ray-emitting CVs, we identify possible orbital modulation for 56 sources in ZTF/TESS light curves. About 51% of the candidates are exclusively selected from the eROSITA catalog, while about 36%, 9%, and 4% are selected from the XMM-Newton, Swift, and ROSAT catalogs, respectively. In the color-color diagram, most of the selected CV candidates are distinguished from the active stars, while some sources are likely classified as eclipsing binary systems rather than CVs. Combining the cross-matching process between X-ray catalogs and Gaia sources with the timing analysis of the ZTF/TESS data is an effective tool to identify the candidates of X-ray-emitting CVs. In particular, the eROSITA observation successfully identified the sources that have been missed in the other three catalogs because of its wide coverage on the sky region and high flux sensitivity. On the other hand, the current flux sensitivity of eROSITA is limited to on the order of ~10^-14^erg/cm^-2^/s. As the first eROSITA catalog is result of the operation in the first six months, it is expected that the future operation will further increase the population of known X-ray-emitting CVs.2025A&A...698A.321Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/698/A321CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)IX/10 : ROSAT All-Sky Bright Source Catalogue (1RXS) (Voges+ 1999)IX/29 : ROSAT All-Sky Survey Faint Source Catalog (Voges+ 2000)IX/30 : Second ROSAT PSPC Catalog (ROSAT, 2000)IX/58 : 2SXPS Swift X-ray tel. point source catalogue (Evans+, 2020)B/swift : Swift Master Catalog (HEASARC, 2004-)B/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-)J/A+A/682/A34 : SRG/eROSITA all-sky survey catalogs (eRASS1) (Merloni+, 2024)J/A+A/687/A305 : CV eROSITA-enhanced multi-wavelength cat.https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/698/A321https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/698/A321http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/698/A321https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/698/A321https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/698/A321http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/698/A321GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/698/A321/cvs (Cataclysmic variable sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/698/A321/cvs?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/698/A321/cvs?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/698/A321/cvs?GETtext/xml+votable180.050000true91.1284926-71.422722870.005555555555555556Cone search capability for table J/A+A/698/A321/cand (Cataclysmic variable candidates)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/698/A321/cand?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/698/A321/cand?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/698/A321/cand?GETtext/xml+votable180.050000true116.8687639054-9.5258054886490.0055555555555555566/283 873 901 974 1253 1639 1720 1902 2035 2248 2737 2885 3029 3269 3292 3908 4144 4296 4453 4790 5210 5485 5918 6052 6076 6314 6671 7040 7043 7070 7211 7342 7371 7659 7828 7930 8552 8559 8630 9267 9333 9476 10055 12466 12477 12625 12627 12762 12933 12943 12977 13234 13286 13575 13595 13686 13902 14170 14415 14433 14608 14641 14723 14781 15150 15255 15365 15694 16070 16072 16701 17515 18844 18859 19297 19592 19943 20523 20773 20797 20833 20845 20883 20894 21088 21194 21255 21419 21522 21603 21605 21659 21822-21823 21917 22140 22150 22216 22385 22424 22485 22615 22683 22771 22798 22828 22987 22989 23050 23056 23070 23152 23301 23549 23790 23871 24126 24164 24217 24283 24417 24480 24604 24794 24895 24942 25232 25587 25934 26102 26588 26979 26995 27221 28104 28194 28675 28681-28683 28686 28690 28699 28701 28703 28709-28711 28720-28721 28726-28727 28746 28751-28752 28787 28794 28798 28808 28822 28827 28874 28884 28973 29006 29072 29193 29217-29218 29234 29278 29288 29307 29352 29675 29910 30306 30553 30682 30706 31185 31331 31681 31689 31699 31770 31774 31804 31827 32216 32273 32436 32645 32862 32901 32956 32972 33067 33078 33106 33222 33378 33486 33546 33574 33713 33765 33831 33874 34066 34076 34085 34094 34357 34558 34617 34666 34697 34758 34864 34901 34986 35081 35165 35530 35700 35766 35824 35864 35960 36008 36129 36910 36948 36980 37022 37026 37057 37111 37150 37191 37233 37238 37247 37278 37441 37490 37504 37539 37555-37556 37560 37562 37567 37611 37622 37627 37752 37784 37827 37851 37911 37928 37933 38016 38033 38043 38058 38089 38100 38115 38123 38139 38156 38264 38273 38285 38292 38308 38364 38451 38492 38526 38565 38675 38733 38813 38827 39253 39404 39434 39514 39531 39547 39694 39697 39714 39779 39805 40119 40173 40201 40415 40474 40577 40615 40640 40658 41166 41224 41226 41270 41311 41341 41371 41381 41402 41421 41446 41543 41582 41586 41627 41637 41652 41713 41729 41761 41945 41965 41997 42039 42133 42306 42314 42323 42333 42337-42338 42382 42425 42596 42625 42650 42653 42679 42831-42832 42841-42842 42844 42867-42868 42879 42910 42915 42965 42973-42974 42989 43030 43032 43110 43260 43269 43321 43374 43403 43454 43548 43595 43597 43656 43659 43724 43796 43854 43882 44072 44278 44436 44614 44660 44665 44992 45098 45447 45666 45696 45763 45814 45830 45855 45963 46002 46028 46153 46237 46493 46726 46969 47131-47132 47181 47215 47240 47255 47269-47270 47319 47496 47537 47693 47696 47801 47866 48277 48500 49043 49112https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/698/A321?format=asciiGamma-rayX-raydefaultJ/A+A/698/A321/cvsCataclysmic variable sourcesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBP-RPDifference between the Gaia blue photometric band (G_bp) and the red photometric band (G_rp) magnitudes in Gaia DR3magphot.color;em.opt.B;em.opt.RdoubleGMAGAbsolute magnitude of the source in Gaia DR3magphys.magAbsdoubleplxParallax of the source in Gaia DR3maspos.parallax.trigdoubleFX? X-ray flux of the source in X-ray catalogs (in erg/cm^2^/s) (1)mW.m**-2phot.flux;em.X-raydoublenullablePer? Period of the source based on light curve of ZTF/TESS or recored in VSXdtime.perioddoublenullableTelSource identified in which telescope (eROSITA, XMM-Newton, Swift or ROSAT)meta.notecharGaiaDR3Source ID in Gaia DR3meta.id;meta.main1eRASSName of the X-ray source (from the X-ray catalog, 1eRASS JHHMMSS.s+DDMMSS)meta.idcharRA_ICRSRight Ascension (ICRS) at Ep=2016.0 of the source in Gaia DR3degpos.eq.ra;meta.mainDE_ICRSDeclination (ICRS) at Ep=2016.0 of the source in Gaia DR3degpos.eq.dec;meta.mainNameName of the source in the SIMBAD astronomical databasemeta.idcharVSXName of the source in the Variable Star Index (VSX) catalogmeta.idcharJ/A+A/698/A321/candCataclysmic variable candidatesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintTelSource identified in which telescope (eROSITA, XMM-Newton, Swift or ROSAT)meta.notecharGaiaDR3Source ID in Gaia DR3meta.id;meta.main1eRASSName of the X-ray source (from the X-ray catalog, 1eRASS JHHMMSS.s+DDMMSS)meta.idcharRA_ICRSRight Ascension (ICRS) at Ep=2016.0 of the source in Gaia DR3degpos.eq.ra;meta.mainDE_ICRSDeclination (ICRS) at Ep=2016.0 of the source in Gaia DR3degpos.eq.dec;meta.mainNameName of the source in the SIMBAD astronomical databasemeta.idcharVSXName of the source in the Variable Star Index (VSX) catalogmeta.idcharBP-RPDifference between the Gaia blue photometric band (G_bp) and the red photometric band (G_rp) magnitudes in Gaia DR3magphot.color;em.opt.B;em.opt.RdoubleGMAGAbsolute magnitude of the source in Gaia DR3magphys.magAbsdoubleplxParallax of the source in Gaia DR3maspos.parallax.trigdoubleFX? X-ray flux of the source in X-ray catalogs (in erg/cm^2^/s) (1)mW.m**-2phot.flux;em.X-raydoublenullablePer? Period of the source based on light curve of ZTF/TESS or recored in VSXdtime.perioddoublenullable