J/other/AstL/51.ivo://CDS.VizieR/J/other/AstL/51.412CDSKhamitov I.M.Bikmaev I.F.Gilfanov M.R.Sunyaev R.A.Medvedev P.S.,Gorbachev M.A.Sklyanov A.S.Efremova P.D.Panarin S.S.2026-04-02T06:28:33Z2026-03-11T08:45:15ZCDS support team

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

cds-question@unistra.fropen-star-clustersx-ray-sourcesUsing data from the all-sky X-ray survey with the eROSITA telescope onboard the SRG orbital observatory and the optical catalog of Hyades cluster members constructed from Gaia data (2023A&A...678A..75Z), we have investigated the X-ray emission from cluster stars. Of the 395 cluster members located in the eastern Galactic part of the sky, eROSITA detects X-ray emission from 290 stars, 171 of which have been found for the first time in X-rays. At the Hyades distance (~47pc) the median eROSITA sensitivity in this sky region corresponds to a 0.3-2.3keV luminosity L_X_~2.6x10^27^erg/s, allowing 100% of the stars with spectral types from F0 to K5 to be detected within the Hyades tidal radius. We have also investigated objects in the Hyades tidal tail (2019A&A...621L...3M, 2019A&A...621L...2R), where X-ray emission was recorded from 114 of the 281 known tidal tail members, 59 of which have been found in X-rays for the first time.2025AstL...51..412Khttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/other/AstL/51.412CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)J/A+A/621/L2 : Hyades tidal tails revealed by Gaia DR2 (Roeser+, 2019)J/A+A/621/L3 : Hyades tidal tails with Gaia DR2 (Meingast+, 2019)J/ApJ/931/45 : The factory + the beehive. IV. Praesepe + Hyades (Nunez+, 2022)J/A+A/678/A75 : Young nearby open clusters members photometry (Zerjal+, 2023)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/other/AstL/51.412https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/other/AstL/51.412http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/other/AstL/51.412https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/other/AstL/51.412https://vizier.iucaa.in/viz-bin/votable?-source=J/other/AstL/51.412http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/other/AstL/51.412GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/other/AstL/51.412/table1 (eROSITA X-ray sources in the Hyades)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/other/AstL/51.412/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/other/AstL/51.412/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/other/AstL/51.412/table1?GETtext/xml+votable180.050000true36.911506717.67235370.005555555555555556Cone search capability for table J/other/AstL/51.412/table7 (eROSITA X-ray sources in the Hyades Eastern Galactic tidal tail)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/other/AstL/51.412/table7?https://vizier.iucaa.in/viz-bin/conesearch/J/other/AstL/51.412/table7?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/other/AstL/51.412/table7?GETtext/xml+votable180.050000true0.653515010269680551.945386582209480.005555555555555556Cone search capability for table J/other/AstL/51.412/table8 (Hyades coincidences of eROSITA and ROSAT sources)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/other/AstL/51.412/table8?https://vizier.iucaa.in/viz-bin/conesearch/J/other/AstL/51.412/table8?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/other/AstL/51.412/table8?GETtext/xml+votable180.050000true60.184661913.90690040.0055555555555555565/80-81 84 87 256 261 5883 5886-5887 6058 6/46 78 95 197 211 247 260 262 265 272 274 276 278 284 287 303 305 309 311 313 318 330 333-335 340-342 344 353 355 357-358 360 363 365 368-369 373 375 378 381-383 401 407 426-427 450 456 458 462 465 470 472 475 478 481 483 488 499 507 608 701 706 770 784 803 823 835 840 847 879 890 917 924 968 987 989 997 1009 1020 1029 1031-1032 1035-1037 1041-1042 1048-1050 1052 1057-1058 1060-1062 1064-1065 1075 1090 1097 1158-1159 1166-1167 1196 1198-1199 1210-1211 1234 1272 1385-1386 1451 1564 1568 1577 1580 1609 1611 1614 1640 1661 1676 1720 1807 1827 1897 2139 2163 2183 2228 2274 2293 2325 2350 2368 2375 2383 2426 2446 2466 2525 2535 2583 2609 2634 2711 2715 2788 2804 2809 2811 2813 2827-2828 2830 2838 2866 2915 2924 2974 3066 3117 3133 6700 6802 12655 13351 13542 13579 13591 13650 13654 13667 13737 13742 13758 13761 13787 13802 13805 13808-13809 13818 13840 13911 13943 14035-14036 14065 14085 14091 14108 14113-14114 14122-14123 14137 14142 14144 14149 14191 14212 14217-14219 14221 14227 14230 14232-14233 14243 14259 14266 14294 15443 18404 18544 19424 19446 19448 20087 20157 23288 23479 23487 23526-23527 23529-23531 23538-23539 24230 24236-24238 24241-24242 24244 24248-24249 24251 24294 24297-24298 24319 24506 24510 24538 24554 367931.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/other/AstL/51.412?format=asciiX-raydefaultJ/other/AstL/51.412/table1eROSITA X-ray sources in the HyadesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLXX-ray luminosity in 0.3-2.3keV band according to 5 eROSITA surveys (in 10^+28^erg/s unit)1e+21Wphys.luminosity;em.X-rayfloate_LX1-sigma error of X-ray luminosity in 0.3-2.3keV band according to 5 eROSITA surveys (in 10^+28^erg/s unit)1e+21Wstat.errorfloatlogRXLog of ratio X-ray in 0.3-2.3keV to bolometric luminosities (4)phys.luminosity;arith.ratiodoubleSRGeSRGe+ designation (JHHMMSS.s+DDMMSS)meta.id;meta.maincharGaiaDR3Gaia DR3 identifier (1)meta.idRA_ICRSGaia DR3 right ascension (ICRS) at Ep=2016.0 (1)degpos.eq.ra;meta.mainDE_ICRSGaia DR3 declination (ICRS) at Ep=2016.0 (1)degpos.eq.dec;meta.mainGmagGaia DR3 G-band mean magnitude (1)magphot.mag;em.optdoubler98eROSITA source position errorarcsecstat.error;posfloatSepSeparation between X-ray eROSITA and optical GAIA DR3 positions of sourcearcsecpos.angDistancefloatNgaia[1/3] Number of GAIA DR3 sources within r98meta.numberintf_Xvar[0-2] Flag on Xvar (2)meta.codeintXvar? Factor of X-ray variability (3)stat.fit.paramdoublenullableSpTypeSpectral type (4)src.spTypecharN6d[1/2] Number of Hyades stars within r98meta.numberintbflag[0/1]? binarity parameter, 1 indicates the system with binaritymeta.codeintnullableJ/other/AstL/51.412/table7eROSITA X-ray sources in the Hyades Eastern Galactic tidal tailrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSRGeSRGe designation (JHHMMSS.s+DDMMSS)meta.id;meta.maincharGaiaDR2Gaia DR2 identifier (1)meta.idRA_ICRS[] Gaia DR2 right ascension (ICRS) at Ep=2015.5) (1)degpos.eq.ra;meta.mainDE_ICRSGaia DR2 declination (ICRS) at Ep=2015.5) (1)degpos.eq.dec;meta.mainGmagGaia DR2 G-band mean magnitude (1)magphot.mag;em.optdoubler98eROSITA source position errorarcsecstat.error;posfloatSepSeparation between X-ray eROSITA and optical Gaia DR2 positions of sourcearcsecpos.angDistancefloatNgaia[1/8] Number of Gaia DR2 sources within r98meta.numberintLXX-ray luminosity in 0.3-2.3keV band according to 5 eROSITA surveys (in 10^+28^erg/s unit)1e+21Wphys.luminosity;em.X-rayfloate_LX1-sigma error of X-ray luminosity in 0.3-2.3keV band according to 5 eROSITA surveys (in 10^+28^erg/s unit)1e+21Wstat.errorfloatlogRXLog of ratio X-ray in 0.3-2.3keV to bolometric luminosities (4)phys.luminosity;arith.ratiodoublef_Xvar[0/2] Flag on Xvar (2)meta.codeintXvar? Factor of X-ray variability (3)stat.fit.paramdoublenullableSpTypeSpectral type (4)src.spTypecharJ/other/AstL/51.412/table8Hyades coincidences of eROSITA and ROSAT sourcesoffaxis? Distance of the ROSAT X-ray source from the telescope axis in arcmin (1)arcminpos.angDistanceintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSRGeSRGe+ designation (JHHMMSS.s+DDMMSS)meta.id;meta.maincharInstrROSAT instrument (1)instrcharSourceSource of X-ray data (1)meta.bibcharRAJ2000Right ascension (J2000) of the ROSAT source (1)degpos.eq.ra;meta.mainDEJ2000Declination (J2000) of the ROSAT source (1)degpos.eq.dec;meta.mainSepSeparation between the ROSAT and eROSITA sourcesarcsecpos.angDistancefloatNgaia[1/2] Number of Gaia DR3 optical counterparts in the r98 error circle of the eROSITA X-ray sourcemeta.numberintFX-ROSAT0.1-2.4keV X-ray flux of the source from the ROSAT (10^-13^erg/s/cm^2^ units) (1)1e-16W.m**-2phot.flux;em.X-rayfloate_FX-ROSATMeasurement error in the X-ray flux of the source from the ROSAT data in the 0.1-2.4keV energy (10^-13^erg/s/cm^2^ units) (1)1e-16W.m**-2stat.errorfloatFX-EroX-ray flux of the source from the eROSITA data in the 0.3-2.3keV energy band (10^-13^erg/s/cm^2^ units)1e-16W.m**-2phot.flux;em.X-rayfloate_FX-EroMeasurement error in the 0.3-2.3keV X-ray flux of the source from the eROSITA data (10^-13^erg/s/cm^2^ units)1e-16W.m**-2stat.errorfloatNero[1/2] Number of eROSITA sources in the Hyades that fell into the error circle of the ROSAT source identified previously with a cluster starmeta.numberint