J/MNRAS/476/1224ivo://CDS.VizieR/J/MNRAS/476/1224doi:10.26093/cds/vizier.74761224CDSArkhypov O.V.Khodachenko M.L.Lammer H.Gudel M.Luftinger T.,Johnstone C.P.2024-08-18T20:18:24Z2021-05-31T13:30:13ZCDS support team

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

cds-question@unistra.frvariable-starsx-ray-sourceseffective-temperatureStellar X-ray emission plays an important role in the study of exoplanets as a proxy for stellar winds and as a basis for the prediction of extreme ultraviolet (EUV) flux, unavailable for direct measurements, which in their turn are important factors for the mass-loss of planetary atmospheres. Unfortunately, the detection thresholds limit the number of stars with the directly measured X-ray fluxes. At the same time, the known connection between the sunspots and X-ray sources allows using of the starspot variability as an accessible proxy for the stellar X-ray emission. To realize this approach, we analysed the light curves of 1729 main-sequence stars with rotation periods 0.5<P<30d and effective temperatures 3236<Teff<7166K observed by the Kepler mission. It was found that the squared amplitude of the first rotational harmonic of a stellar light curve may be used as a kind of activity index. This averaged index revealed practically the same relation with the Rossby number as that in the case of the X-ray to bolometric luminosity ratio R_x_. As a result, the regressions for stellar X-ray luminosity L_x_(P, T_eff_) and its related EUV analogue L_EUV_ were obtained for the main-sequence stars. It was shown that these regressions allow prediction of average (over the considered stars) values of log(L_x_) and log(L_EUV_) with typical errors of 0.26 and 0.22dex, respectively. This, however, does not include the activity variations in particular stars related to their individual magnetic activity cycles.2018MNRAS.476.1224Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/476/1224CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/133 : Kepler Input Catalog (Kepler Mission Team, 2009)J/ApJ/743/48 : Stars with rotation periods & X-ray luminosities (Wright+ 2011)J/A+A/557/L10 : Rotation periods of 12000 Kepler stars (Nielsen+, 2013)J/ApJS/211/24 : Rotation periods of Kepler MS stars (McQuillan+, 2014)J/ApJS/229/30 : Q1-17 Kepler targets revised stellar properties (Mathur+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/476/1224https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/476/1224http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/476/1224https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/476/1224https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/476/1224http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/476/1224GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/476/1224/table1 (The analysed stellar set, applied parameters, and predictions)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/476/1224/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/476/1224/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/476/1224/table1?GETtext/xml+votable180.050000true291.1632736.627590.005555555555555556Cone search capability for table J/MNRAS/476/1224/table3 (Parameters and predictions for stars in the catalogue by Wright et al. (2011ApJ...743...48W, Cat. J/ApJ/743/48))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/476/1224/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/476/1224/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/476/1224/table3?GETtext/xml+votable180.050000true4/911 922 933 5/118 784 3683 3692-3694 3729-3731 3737-3741 3776-3778 6/49 137 254 331 336 340-342 348 350 358 368 373 383 456 461-463 470 485 487 496 546 684 701 781 838 847 850 861 867 965 983 989 999 1030 1045 1048 1052 1058 1066-1067 1079 1099 1105 1122 1133 1146 1148 1159 1165 1181 1199 1205 1212 1234 1255 1264 1273 1511 1556 1559-1560 1569 1571-1572 1599 1605 1611 1613 1646 1665 1723 1768 1770-1771 1774 1819 1853 1873 1875 1880 1890 1948 2072 2298 2321 2335 2366 2422 2468 2494 2498 2534 2596-2597 2616 2651-2652 2660 2671 2755-2756 2783 2793 2800 2816 2858 2952 2974 3093-3095 3140 3144 3383 3639 3697 4128 4444 4468 4591 4696 4698-4699 4720-4721 4773 5074 5095 5108 5119 5319 5331 5387 5399 5413 5420 5438 5452 5487 5504 5532 5534 5670 5743 5787-5788 5802 5819 5822 5850 5853 5872 5895 5915 5917 5927 6231 6245 6295 6385 6410 6522 6543 6561 6599 6606 6660 6725-6726 6836 6847 6850 6853 7189 7202 7264 7763 8224 8357 8440 8627 8790 8843 9086 9167-9168 9200 9281 9293-9294 9311 9316 9332 9445 9485 9570 9597 9599 9616 9682-9683 9687 9689 9712 9753 9759 9770 9773 9797 9831 9844 9856 9902 9905 9912 9923 9926 9929 9954 10005 10016 10027-10028 10225 10303 10375 10481 10490 10538 10771 10792 10893 10905 10912 10928 11015 11128 11510 11856 12092 12341 12343 12454 12464 12592 12676 12683 12792 12924 12944 12983 13096 13122 13301 13451 13495 13499 13536 13541 13547-13548 13625 13713 13728 13743 13748 13750 13763 13792 13795 13802 13855 13946 14038 14208 14266 14551 14555-14556 14558 14567 14571-14573 14575 14631 14635-14638 14640 14642 14720-14722 14730-14731 14738 14744 14746 14749-14751 14780-14782 14792 14794-14795 14816 14865 14871 14876-14877 14887 14893 14897 14904 14912 14914-14915 14946-14947 14968-14969 14971-14972 14974 14978 15007 15009-15010 15021 15028 15040-15041 15044-15045 15057 15060 15062 15116 15120-15122 15136-15137 15227 15703 16041 16164 17019 17058 17124 17137 17219 17541 17552 18139 18295 18553 18623 19912 20071 20145 20332 20716 21050 21177 21386 21956 22146 22148 22289 22461 22510 22709 22807 22873 22964 23011 23094 23140 23230 23342 23429 23444 23457 23479 23490 23492 23497 23499 23501 23504 23506 23511 23515 23525 23527 23532-23533 23535 23537-23539 23544-23545 23547-23548 23550 23564 23661 23731 23878 23887 23892 23895 24053 24102 24151 24160 24201 24207 24227 24234 24237 24242 24312-24313 24541 24924 25192 25405 25444 25521 25793 26133 26279 26327 26521 26555 26761 26997 27201 27395 27762 27973 27980 28123 28180 28341 28395 28605 28646 28955 29196 29978 30176 30540 30965 31087 31101 31104 31130 31132 31425 31478 31667 31751 32067 32247 32431 32500 32505 32606 32617-32618 32630 32633 32650 32660 32676 32683 32699-32700 32715 32732 32743 32757 33116 33937 34074 35150 35950 36057 36483 36487 36511 36577 36664 36697 36713 36762 37229-37231 37240 37242 37316-37317 37419 37592-37593 37787-37788 37790-37791 38168 38247 38430 38551 39181 39183 40739 40784 41591 41763 42290 42420 42683 44226 44228 44316 45269 46598 46925 46987 48230 48263 48274 48394 48905https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/476/1224?format=asciiX-raydefaultJ/MNRAS/476/1224/table1The analysed stellar set, applied parameters, and predictionsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC numbermeta.id;meta.mainintTeffStellar effective temperature from Mathur et al. (2017ApJS..229...30M, Cat. J/ApJS/229/30)Kphys.temperature.effectiveintPRotation period (1)dtime.periodfloatlog(<A12>)Our active index, averaged over a whole light curve, A_1_^2^spect.indexdoublee_log(<A12>)Estimated error of log(<A12>)stat.errordouble(B-V)oColour index according to the transformation Teff-->(B-V)o in equation (1)magphot.color;em.opt.B;em.opt.VdoubletauMLTTurnover time according to equation (4) in Noyes et al. (1984ApJ...279..763N)dtime.epochdoublelog(Rx)regLogarithm of the ratio of X-ray to bolometric luminosities which are estimated from equations (6)-(8) of the paperphys.luminosity;arith.ratiodoublelog(Lx)regLogarithm of the predicted X-ray luminosity using equations (10)-(14) of the paperlog(1e-07W)phys.luminosity;em.X-raydoubleSimbadSimbad column added by the CDSmeta.ref.urlchar_RAPositions from KIC (right ascension part)degpos.eq.ra;meta.main_DEPositions from KIC (declination part)degpos.eq.dec;meta.mainJ/MNRAS/476/1224/table3Parameters and predictions for stars in the catalogue by Wright et al. (2011ApJ...743...48W, Cat. J/ApJ/743/48)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000? Right ascension (J2000) for epoch 2000.0 (1)degpos.eq.ra;meta.mainnullableDEJ2000? Declination (J2000) for epoch 2000.0 (1)degpos.eq.dec;meta.mainnullableFieldAfiliationmeta.id.parentcharTeffEffective temperature (1)Kphys.temperature.effectiveintPPeriod (1)dtime.periodfloattauMLTTurnover time (2)dtime.epochdoublelog(Rx)regLogarithm of the ratio of X-ray to bolometric luminosities which are estimated from equations (6)-(8) of the paperphys.luminosity;arith.ratiodoublelog(Lx)regLogarithm of the predicted X-ray luminosity using equations (10)-(14) of the paperlog(1e-07W)phys.luminosity;em.X-rayfloatlog(Lx)Logarithm of the measured X-ray luminosity (1)log(1e-07W)phys.luminosity;em.X-rayfloatW2011Display the Wright et al. (2011, Cat J/ApJ/743/48) datameta.ref.urlchar