J/A+A/694/A157ivo://CDS.VizieR/J/A+A/694/A157doi:10.26093/cds/vizier.36940157CDSSu T.Zhang L.Han X.L.Misra P.Zhu Z.Pi Q.2025-05-21T20:01:29Z2025-02-11T09:37:49ZCDS support team

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

cds-question@unistra.frstellar-activityeffective-temperatureradial-velocitychemical-abundancesline-intensitiesstellar-massesStellar chromospheric activity can impact the search for exoplanets. Earth 2.0 (ET 2.0) is a space telescope designed for exoplanet detection. This work surveys stellar chromospheric activity in the ET2.0 target regions to enhance the detection rate of exoplanets. This work uses Halpha and Ca ii H&K lines as indicators of chromospheric activity and conducts a survey of stellar chromospheric activity in the ET2.0 target regions using LAMOST low- and medium-resolution spectra. After cross-referencing with the ET 2.0 input catalog, we obtained over 349000 low-resolution spectra and over 30000 medium-resolution spectra from LAMOST. We quantified the chromospheric activity intensity for all spectra and selected the results for those with a signal-to-noise ratio (S/N) above 10 for further study of chromospheric activity. The quantification standards include equivalent width (EW) and the ratio of bolometric luminosity to the corresponding spectral line luminosity (L_Halpha_/L_bol_, L_CaH_/L_bol_, L_CaK_/L_bol_, L_HK_/L_bol_). Utilizing Halpha and CaII H&K lines, we evaluate chromospheric activity for over 320000 and 110000 spectra based on LAMOST low-resolution spectra, respectively. Additionally, we evaluated chromospheric activity for 34000 spectra using Halpha lines based on medium-resolution spectra. And select samples suitable for exoplanet studies based on Halpha and CaII H&K lines. Additionally, we explore the relationship between stellar activity observed by LAMOST and rotation periods obtained from Kepler and TESS surveys. Our findings confirm the presence of two distinct regions in the relationship between stellar activity and Rossby number (Ro): saturated and unsaturated. We determined a critical Ro in the range of 0.09 to 0.12 using r-band spectra of 11921 stars and u-band spectra of 6120 stars. Moreover, we observe that CaII H&K lines exhibit greater sensitivity to Ro in the unsaturated region compared to Halpha line measurements. Lastly, we establish positive correlations between various activity indicators, including R'_CaK_, R'_CaH_, R'_HK_ and R'_Halpha_.2025A&A...694A.157Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/694/A157CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/156 : LAMOST DR7 catalogs (Luo+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/694/A157https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/694/A157http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/694/A157https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/694/A157https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/694/A157http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/694/A157GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/694/A157/tablea1 (Low-resolution spectral parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/694/A157/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/694/A157/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/694/A157/tablea1?GETtext/xml+votable180.050000true292.920458337.97330560.005555555555555556Cone search capability for table J/A+A/694/A157/tablea2 (Medium-resolution spectral parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/694/A157/tablea2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/694/A157/tablea2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/694/A157/tablea2?GETtext/xml+votable180.050000true278.40637540.43377780.0055555555555555562/58 3/226 4/814 826 900-901 911 916 920 922-924 926 944-946 954-955 958 992 2033 2037-2039 2045 2047 5/2389 2391 2397 2399 2421 2423 3251 3261-3263 3275 3297-3298 3300 3302-3303 3311 3320 3322-3323 3587-3588 3590-3591 3594-3595 3597-3599 3608-3610 3612-3613 3635 3638-3639 3641 3643 3648 3650 3653 3655 3657-3659 3661 3670-3673 3675-3678 3686-3687 3701-3703 3708-3710 3788-3790 3792 3794 3799 3805 3814-3815 3825-3828 3850 3872-3874 8031 8047 8051 8053-8058 8060-8061 8063 8131 8137 8140 8142-8144 8147 8165 8176 8178-8179 8185 6/9553 9717 9719 9725 9727 10069 10071 10077 10079 10101 10103 10109 10111 10197 10199 10205 12922 12981 12983 12986-12987 12997-12999 13001-13003 13008 13010 13016 13022-13023 13040 13042-13043 13094-13095 13097 13099 13112 13114-13115 13185 13197-13199 13204 13206-13207 13239 13256 13284 13286-13287 13304 13306 14341-14343 14345 14347 14358 14370-14371 14373 14375 14385-14387 14444 14446 14461 14463 14528-14530 14535-14536 14538-14539 14546-14547 14549 14551 14560-14561 14563 14569-14570 14617 14619 14624 14626-14627 14641-14643 14648-14650 14652-14653 14673-14676 14678-14679 14696-14697 14699 14716 14719 14736 14738-14739 14743 14800 14802-14803 14844-14846 15164-15165 15172-15174 15180 15182 15184-15185 15189-15191 15193 15195 15200-15202 15215 15217 15226-15227 15230 15232-15234 15236 15240 15242-15243 15245-15247 15255 15297-15299 15316 15320-15322 15344 15346-15347 15352 15354 15368 15370-15371 15392-15393 15404 15406-15407 15500-15502 15520 15522 15904-15906 15908 32119 32181-32183 32185-32187 32197-32199 32201-32203 32208 32210-32211 32249-32251 32517-32519 32521-32523 32545 32557 32564 32566-32567 32581-32585 32587 32657 32669 32708-32709 32711 32737 327491.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/694/A157?format=asciidefaultJ/A+A/694/A157/tablea1Low-resolution spectral parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintVEWHaHalpha line variationspect.line.intensity;arith.ratiocharVEWCaIIKCaII K line variationspect.line.intensity;arith.ratiocharVEWCaIIHCaII H line variationspect.line.intensity;arith.ratiocharLAMOSTLAMOST name (JHHMMSS.ss+DDMMSS.s)meta.id;meta.maincharExpTimeSpectral exposure timestime.duration;obs.exposurefloatsnru? u-band signal-to-noise ratiostat.snr;pos.cartesian.xintnullablesnrg? g-band signal-to-noise ratiostat.snrintnullablesnrr? r-band signal-to-noise ratiostat.snrintnullablesnri? i-band signal-to-noise ratiostat.snrintnullablesnrz? g-band signal-to-noise ratiostat.snrintnullableGmag? G-band magnitude in Gaia DR3magphot.mag;em.optfloatnullablesubclassStellar spectral typesrc.spTypecharTeff? Effective temperatureKphys.temperature.effectiveintnullablee_Teff? Error in TeffKstat.error;phys.temperature.effectiveintnullablelogg? Surface gravitylog(cm.s**-2)phys.gravityfloatnullablee_logg? Error in logglog(cm.s**-2)stat.errorfloatnullable[Fe/H]? Metallicityphys.abund.Zfloatnullablee_[Fe/H]? Error in [Fe/H]stat.error;phys.abund.FefloatnullableRVLAMOST? Radial velocitykm/sphys.veloc;pos.heliocentricfloatnullablee_RVLAMOST? Error in Radial velocitykm/sstat.errorfloatnullableEWHa? The equivalent width of the Halpha line0.1nmspect.line.eqWidthdoublenullablee_EWHa? Error in EWHa0.1nmstat.errordoublenullableEWCaK? The equivalent width of the CaII K line0.1nmspect.line.eqWidthfloatnullablee_EWCaK? Error in EWCaK0.1nmstat.errorfloatnullableEWCaH? The equivalent width of the CaII H line0.1nmspect.line.eqWidthfloatnullablee_EWCaH? Error in EWCaH0.1nmstat.errorfloatnullableSindex? The S-index derived from the CaII H & K linesspect.indexfloatnullablee_Sindex? Error in Sindexstat.errorfloatnullableProt? Stellar rotation perioddtime.perioddoublenullableMass? Stellar masssolMassphys.massfloatnullableRo? Rossby numberstat.paramdoublenullableP[0/4]? Observation prioritymeta.codeintnullable_RAPositinos from LAMOST name (right ascension part)degpos.eq.ra;meta.mainindexed_DEPositinos from LAMOST name (declination part)degpos.eq.dec;meta.mainindexedHJDHeliocentric Julian Datedtime.epochdoubleindexedJ/A+A/694/A157/tablea2Medium-resolution spectral parametersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintLAMOSTLAMOST name (JHHMMSS.ss+DDMMSS.s)meta.id;meta.maincharHJD? Heliocentric Julian Datedtime.epochdoublenullableindexedSNRSignal-to-noise ratiostat.snrintTeff? Effective temperatureKphys.temperature.effectiveintnullablee_Teff? Error in effective temperatureKstat.error;phys.temperature.effectiveintnullablelogg? Surface gravitylog(cm.s**-2)phys.gravityfloatnullablee_[Fe/H]? Error in [Fe/H]stat.error;phys.abund.Fefloatnullablee_logg? Error in surface gravitylog(cm.s**-2)stat.errorfloatnullable[Fe/H]? Metallicityphys.abund.ZfloatnullableEWHaThe equivalent width of the Halpha line0.1nmspect.line.eqWidthdoublee_EWHaError in EW_Halpha0.1nmstat.errordoubleVEWHaHalpha line variationspect.line.intensity;arith.ratiocharProt? Stellar rotation periodmeta.notedoublenullableMass? Stellar masssolMassphys.massfloatnullablee_Mass? Error in MasssolMassstat.error;phys.massfloatnullableRo? Rossby numberstat.paramdoublenullable_RAPositinos from LAMOST name (right ascension part)degpos.eq.ra;meta.mainindexed_DEPositinos from LAMOST name (declination part)degpos.eq.dec;meta.mainindexed