X-ray activity of nearby G-, K-, and M-type starsJ/A+A/694/A93ivo://CDS.VizieR/J/A+A/694/A93doi:10.26093/cds/vizier.36940093CDSZhu E.Preibisch T.2026-03-03T20:01:14Z2025-02-05T08:49:02ZCDS support teamCDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, Francecds-question@unistra.frx-ray-sourcesm-starsThe intense X-ray and UV emission of some active M stars has raised questions about the habitability of planets around M-type stars. We aim to determine the unbiased distribution of X-ray luminosities in complete, volume-limited samples of nearby M dwarfs, and compare them to those of K and G dwarfs. We have constructed volume-complete samples of 205 M stars with spectral type <=M6 within 10pc from the Sun, 129 K stars within 16pc, and 107 G stars within 20pc. We use X-ray data from Chandra, XMM-Newton, eROSITA, and ROSAT to obtain the X-ray luminosities of the stars. Our samples reach an X-ray detection completeness of 85%, 86%, and 80% for M, K, and G stars. The fractional X-ray luminosities, log(LX/Lbol), of the M stars show a bimodal distribution with one peak at around ~5, mostly contributed by early M stars (M0-M4), and another peak around ~3.5, contributed mainly by M4-M6 stars. The comparison of the different spectral classes shows that 63% of all M stars in our sample (80% of the M stars with spectral type <M4) have LX/Lbol values that are within the central 80% quantile of the distribution function for G stars. 55% of all M stars in our sample (and 72% of the M stars with spectral type <M4) have LX/Lbol less than 10 times the solar value. The X-ray activity levels of the majority (~>60%) of nearby M dwarfs no later than M6 are actually not higher than the typical (80% quantile) levels for G-type stars. The X-ray irradiation of habitable-zone planets around these stars should therefore not present a specific problem for their habitability.2025A&A...694A..93Zhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/694/A93CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/670/A19 : Fifth Catalogue of Nearby Stars (CNS5) (Golovin+, 2023)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/694/A93https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/694/A93http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/694/A93https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/694/A93https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/694/A93http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/694/A93GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/694/A93/g-xray (X-ray data of nearby G stars (table F1))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/694/A93/g-xray?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/694/A93/g-xray?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/694/A93/g-xray?GETtext/xml+votable180.050000true219.920408130103-60.8351452189750.005555555555555556Cone search capability for table J/A+A/694/A93/k-xray (X-ray data of nearby K stars (table F1))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/694/A93/k-xray?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/694/A93/k-xray?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/694/A93/k-xray?GETtext/xml+votable180.050000true219.920408130103-60.8351452189750.005555555555555556Cone search capability for table J/A+A/694/A93/m-xray (X-ray data of nearby M stars (table F1))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/694/A93/m-xray?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/694/A93/m-xray?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/694/A93/m-xray?GETtext/xml+votable180.050000true217.392321472009-62.67607511676670.0055555555555555566/4 22 131 137 250 309 377 527 546 684 725 811 1033 1341 1875 1938 2317 2476 2724 2737 2747 2923 3005 3020 3345 3638-3639 3715 3719 3751 3791 4158 4444 4462 5009 5074 5207 5304 5333 5377 5420 5522 5534 5590 5670 5836 5853 5899 6066 6308 6552 6672 6726 6894 6974 7103 7264 7395 7512 7665 7763 7950 8023 8094 8123 8281 8440 8466 8591 8788 8790 8845 9072 9128 9327 9339 9403 9476 9585 9629 9662 9696 9801 9811 9835 10027 10037 10149 10225 10313 10375 10448 10735 10899 11142 11290 11405 11632 11636 11806 12232 12340 12454 12592 12679 12865 12944 13025 13301 13451 13688 13743 13875 14266 14278 14419 14515 14539 14650 14772 15311 15346 15355 15548 15597 15602 15651 15861 15960 15962 16041 16069 16391 16502 16678 16689 16692 16754 16758 16827 17017 17028 17058 17348 17425 18139 18268 18440 18450 18496 18666 18761 19466 19912 20071 20100 20145 20278 20328 20459 20507 20701 20753 20896 21060 21136 21149 21151 21177 21484 21568 21726 21925 21953 22014 22040 22148 22289 22309 22325 22645 22708 22739 22807 22813 22818 22836 23047 23056 23137 23230 23564 23575 23661 23735 23774 23867 23910 23960 23997 24028 24117 24151 24212 24227 24239 24616 24713 24729 24777 24924 25009 25192 25407 25820 25966 26279 26327 26379 26462 26487 26521 26538 26560 26575 26583 26972 27201 27289 27374 27392 27459 27462 27731 27762 27954 27973 28122 28343 28548 28605 28646 28664 28696 28955 28987 29084 29196 29458 29467 29684 30176 30257 30455 30505 30529 30665 30771 30833 30878 30965 31011 31019 31029 31073 31087 31101 31130 31393 31399 31433 31478 31751 31781 32115 32229 32335 32645 32757 32848 32930 33116 33281 33425 33442 33533 33552 33813 33818 33849 33964-33965 34181 34345 34446 34448 34896 35079-35080 35150 35247 35351 35434 35670 35753 35802 35948 36248 36288 36365 36511 36526 36614 36664 36693 36697 36735 36971 37122 37257 37332 37377 37379 37408 37902 38219 38238 38456 38461 38551 39154 39284 39331 39441 39499-39500 40078 40250 40496 40505 40515 40692 40801 40932 41460 41463 41591 41687 41763 41941 42022 42054 42248 42255 42285 42290 42314 42420 42426 42459 42595 42652 42700 42760 42784 43187 43411 43413 43580 43723 43804 43851 43989 44284 44437 44482 44681 44921 44937 45322 45334 45412 45564 45668-45669 45941 45982 46244 46247 46566 46632 46640 46718 46776 46925 46956 46997 47061 47137 47347 47414 47453 47589 47740 47758 47910 48173 48254 48263 48274 48291 48549 48652 48705 48768 48788 48906 48985https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/694/A93?format=asciiX-raydefault
J/A+A/694/A93/g-xrayX-ray data of nearby G stars (table F1)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSimbadNameSimbad column added by the CDSmeta.idcharnullableCNS5? Designation in CNS5meta.id;meta.mainintnullableGJ? Gliese-Jahreiss numbermeta.idfloatnullableONameName of stars that do not have CNS5 and GJmeta.idcharCompComponent in a multiple systemmeta.code.multipcharRAJ2000Right ascension (J2000) (Gaia DR3)degpos.eq.ra;meta.mainDEJ2000Declination (J2000) (Gaia DR3)degpos.eq.dec;meta.mainfGaia[0/1] Flag for stars with peculiar Gaia coloursmeta.codeintSpTypeSpectral typesrc.spTypecharr_SpTypeReference of SpTypemeta.ref;pos.framecharGSpTypeSpectral type according to M_G_ which is different from literature SpTypesrc.spTypecharDistanceGaia DR3 distance to the Sunpcpos.distancedoubleLXeROSITA? X-ray luminosity according to eROSITA1e-07Wphys.luminosity;em.X-raydoublenullableE_LXeROSITA? Upper error of LXeROSITA1e-07Wstat.error;stat.maxdoublenullablee_LXeROSITA? Lower error of LXeROSITA1e-07Wstat.errordoublenullablef_LXeROSITA[0/1]? Flag for LXeROSITA as upper limit value (1 = yes)meta.codefloatnullableBandLXeROSITAEnergy band of LXeROSITAkeVinstr.bandwidthcharr_LXeROSITAReference of LXeROSITAmeta.ref;pos.framecharLXROSAT? X-ray luminosity according to ROSAT1e-07Wphys.luminosity;em.X-raydoublenullableE_LXROSAT? Upper error of LXROSAT1e-07Wstat.error;stat.maxdoublenullablee_LXROSAT? Lower error of LXROSAT1e-07Wstat.errordoublenullablef_LXROSAT[0/1]? Flag for LXROSAT as upper limit value (1 = yes)meta.codefloatnullableBandLXROSATEnergy band of LXROSATkeVinstr.bandwidthcharInstLXROSATCamera of ROSAT usedmeta.id;instrcharr_LXROSATReference of LXROSATmeta.ref;pos.framecharLXother? X-ray luminosity according to other telescopes (Chandra or XMM-Newton)1e-07Wphys.luminosity;em.X-raydoublenullableE_LXother? Upper error of LXother1e-07Wstat.error;stat.maxdoublenullablee_LXother? Lower error of LXother1e-07Wstat.errordoublenullablef_LXother[0/1]? Flag for LXother as upper limit value (1 = yes)meta.codefloatnullableBandLXotherEnergy band of LXotherkeVinstr.bandwidthcharInstLXotherCamera of other telescopes usedmeta.id;instrcharr_LXotherReference of LXothermeta.ref;pos.framecharLXfinal? X-ray luminosity used in the analysis, converted to ROSAT energy band1e-07Wphys.luminosity;em.X-raydoublenullableE_LXfinal? Upper error of LXfinal1e-07Wstat.error;stat.maxdoublenullablee_LXfinal? Lower error of LXfinal1e-07Wstat.errordoublenullablef_LXfinal[0/1]? Flag for LXfinal as upper limit value (1 = yes)meta.codefloatnullableLbol? Bolometric luminosity1e-07Wphys.luminositydoublenullabler_LbolReference of _bolmeta.ref;pos.framecharLX/Lbol? LX/Lbol used in the final analysisphys.luminosity;arith.ratiodoublenullableE_LX/Lbol? Upper error of LX/Lbolstat.error;stat.maxdoublenullablee_LX/Lbol? Lower error of LX/Lbolstat.errordoublenullable
J/A+A/694/A93/k-xrayX-ray data of nearby K stars (table F1)CompComponent in a multiple systemmeta.code.multipcharRAJ2000Right ascension (J2000) (Gaia DR3)degpos.eq.ra;meta.mainDEJ2000Declination (J2000) (Gaia DR3)degpos.eq.dec;meta.mainfGaia[0/1] Flag for stars with peculiar Gaia coloursmeta.codeintSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCNS5? Designation in CNS5meta.id;meta.mainintnullableGJ? Gliese-Jahreiss numbermeta.idfloatnullableONameName of stars that do not have CNS5 and GJmeta.idcharSpTypeSpectral typesrc.spTypecharr_SpTypeReference of SpTypemeta.ref;pos.framecharGSpTypeSpectral type according to M_G_ which is different from literature SpTypesrc.spTypecharDistanceGaia DR3 distance to the Sunpcpos.distancedoubleLXeROSITA? X-ray luminosity according to eROSITA1e-07Wphys.luminosity;em.X-raydoublenullableE_LXeROSITA? Upper error of LXeROSITA1e-07Wstat.error;stat.maxdoublenullablee_LXeROSITA? Lower error of LXeROSITA1e-07Wstat.errordoublenullablef_LXeROSITA[0/1]? Flag for LXeROSITA as upper limit value (1 = yes)meta.codefloatnullableBandLXeROSITAEnergy band of LXeROSITAkeVinstr.bandwidthcharr_LXeROSITAReference of LXeROSITAmeta.ref;pos.framecharLXROSAT? X-ray luminosity according to ROSAT1e-07Wphys.luminosity;em.X-raydoublenullableE_LXROSAT? Upper error of LXROSAT1e-07Wstat.error;stat.maxdoublenullablee_LXROSAT? Lower error of LXROSAT1e-07Wstat.errordoublenullablef_LXROSAT[0/1]? Flag for LXROSAT as upper limit value (1 = yes)meta.codefloatnullableBandLXROSATEnergy band of LXROSATkeVinstr.bandwidthcharInstLXROSATCamera of ROSAT usedmeta.id;instrcharr_LXROSATReference of LXROSATmeta.ref;pos.framecharLXother? X-ray luminosity according to other telescopes (Chandra or XMM-Newton)1e-07Wphys.luminosity;em.X-raydoublenullableE_LXother? Upper error of LXother1e-07Wstat.error;stat.maxdoublenullablee_LXother? Lower error of LXother1e-07Wstat.errordoublenullablef_LXother[0/1]? Flag for LXother as upper limit value (1 = yes)meta.codefloatnullableBandLXotherEnergy band of LXotherkeVinstr.bandwidthcharInstLXotherCamera of other telescopes usedmeta.id;instrcharr_LXotherReference of LXothermeta.ref;pos.framecharLXfinal? X-ray luminosity used in the analysis, converted to ROSAT energy band1e-07Wphys.luminosity;em.X-raydoublenullableE_LXfinal? Upper error of LXfinal1e-07Wstat.error;stat.maxdoublenullablee_LXfinal? Lower error of LXfinal1e-07Wstat.errordoublenullablef_LXfinal[0/1]? Flag for LXfinal as upper limit value (1 = yes)meta.codefloatnullableLbol? Bolometric luminosity1e-07Wphys.luminositydoublenullabler_LbolReference of _bolmeta.ref;pos.framecharLX/Lbol? LX/Lbol used in the final analysisphys.luminosity;arith.ratiodoublenullableE_LX/Lbol? Upper error of LX/Lbolstat.error;stat.maxdoublenullablee_LX/Lbol? Lower error of LX/Lbolstat.errordoublenullable
J/A+A/694/A93/m-xrayX-ray data of nearby M stars (table F1)DEJ2000Declination (J2000) (Gaia DR3)degpos.eq.dec;meta.mainfGaia[0/1] Flag for stars with peculiar Gaia coloursmeta.codeintSpTypeSpectral typesrc.spTypecharr_SpTypeReference of SpTypemeta.ref;pos.framecharSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintCNS5? Designation in CNS5meta.id;meta.mainintnullableGJ? Gliese-Jahreiss numbermeta.idfloatnullableONameName of stars that do not have CNS5 and GJmeta.idcharCompComponent in a multiple systemmeta.code.multipcharRAJ2000Right ascension (J2000) (Gaia DR3)degpos.eq.ra;meta.mainGSpTypeSpectral type according to M_G_ which is different from literature SpTypesrc.spTypecharDistanceGaia DR3 distance to the Sunpcpos.distancedoubleLXeROSITA? X-ray luminosity according to eROSITA1e-07Wphys.luminosity;em.X-raydoublenullableE_LXeROSITA? Upper error of LXeROSITA1e-07Wstat.error;stat.maxdoublenullablee_LXeROSITA? Lower error of LXeROSITA1e-07Wstat.errordoublenullablef_LXeROSITA[0/1]? Flag for LXeROSITA as upper limit value (1 = yes)meta.codefloatnullableBandLXeROSITAEnergy band of LXeROSITAkeVinstr.bandwidthcharr_LXeROSITAReference of LXeROSITAmeta.ref;pos.framecharLXROSAT? X-ray luminosity according to ROSAT1e-07Wphys.luminosity;em.X-raydoublenullableE_LXROSAT? Upper error of LXROSAT1e-07Wstat.error;stat.maxdoublenullablee_LXROSAT? Lower error of LXROSAT1e-07Wstat.errordoublenullablef_LXROSAT[0/1]? Flag for LXROSAT as upper limit value (1 = yes)meta.codefloatnullableBandLXROSATEnergy band of LXROSATkeVinstr.bandwidthcharInstLXROSATCamera of ROSAT usedmeta.id;instrcharr_LXROSATReference of LXROSATmeta.ref;pos.framecharLXother? X-ray luminosity according to other telescopes (Chandra or XMM-Newton)1e-07Wphys.luminosity;em.X-raydoublenullableE_LXother? Upper error of LXother1e-07Wstat.error;stat.maxdoublenullablee_LXother? Lower error of LXother1e-07Wstat.errordoublenullablef_LXother[0/1]? Flag for LXother as upper limit value (1 = yes)meta.codefloatnullableBandLXotherEnergy band of LXotherkeVinstr.bandwidthcharInstLXotherCamera of other telescopes usedmeta.id;instrcharr_LXotherReference of LXothermeta.ref;pos.framecharLXfinal? X-ray luminosity used in the analysis, converted to ROSAT energy band1e-07Wphys.luminosity;em.X-raydoublenullableE_LXfinal? Upper error of LXfinal1e-07Wstat.error;stat.maxdoublenullablee_LXfinal? Lower error of LXfinal1e-07Wstat.errordoublenullablef_LXfinal[0/1]? Flag for LXfinal as upper limit value (1 = yes)meta.codefloatnullableLbol? Bolometric luminosity1e-07Wphys.luminositydoublenullabler_LbolReference of _bolmeta.ref;pos.framecharLX/Lbol? LX/Lbol used in the final analysisphys.luminosity;arith.ratiodoublenullableE_LX/Lbol? Upper error of LX/Lbolstat.error;stat.maxdoublenullablee_LX/Lbol? Lower error of LX/Lbolstat.errordoublenullable