J/ApJ/871/187ivo://CDS.VizieR/J/ApJ/871/187doi:10.26093/cds/vizier.18710187CDSNamekata K.Maehara H.Notsu Y.Toriumi S.Hayakawa H.Ikuta K.,Notsu S.Honda S.Nogami D.Shibata K.2020-05-19T10:17:30Z2020-04-21T13:12:53ZCDS support team

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

cds-question@unistra.frg-starsstellar-radiimagnetic-fieldseffective-temperatureActive solar-type stars show large quasi-periodic brightness variations caused by stellar rotation with star spots, and the amplitude changes as the spots emerge and decay. The Kepler data are suitable for investigations of the emergence and decay processes of star spots, which are important to understand the underlying stellar dynamo and stellar flares. In this study, we measured the temporal evolution of the star-spot area with Kepler data by tracing the local minima of the light curves. In this analysis, we extracted the temporal evolution of star spots showing clear emergence and decay without being disturbed by stellar differential rotation. We applied this method to 5356 active solar-type stars observed by Kepler and obtained temporal evolution of 56 individual star spots. We calculated the lifetimes and emergence/decay rates of the star spots from the obtained temporal evolution of the spot area. As a result, we found that the lifetimes (T) of star spots range from 10 to 350days when the spot areas (A) are 0.1%-2.3% of the solar hemisphere. We also compared them with sunspot lifetimes and found that the lifetimes of star spots are much shorter than those extrapolated from an empirical relation of sunspots (T{propto}A), while being consistent with other research on star-spot lifetimes. The emergence and decay rates of star spots are typically 5x10^20^Mx/hr (8MSH/hr) with an area of 0.1%-2.3% of the solar hemisphere and mostly consistent with those expected from sunspots, which may indicate the same underlying processes.2019ApJ...871..187Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/871/187CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/133 : Kepler Input Catalog (Kepler Mission Team, 2009)J/other/A+ARV/17.251 : Stars observed with Doppler imaging (Strassmeier, 2009)J/ApJS/197/2 : Transit timing observations from Kepler. I. (Ford+, 2011)J/other/Nat/485.478 : Superflares on solar-type stars (Maehara+, 2012)J/ApJS/209/5 : Superflares of Kepler stars. I. (Shibayama+, 2013)J/ApJ/783/123 : Surface gravity for 220 Kepler stars (Campante+, 2014)J/ApJS/211/24 : Rotation periods of Kepler MS stars (McQuillan+, 2014)J/ApJ/833/170 : Spots parameters for LCs of the EB star KIC 6048106 (Lee, 2016)J/AJ/152/158 : Final Kepler transiting planet search (DR25) (Twicken+, 2016)J/A+A/601/A67 : Kepler solar-type stars modeling (Creevey+, 2017)J/ApJ/851/91 : Statistical studies solar white-light flares (Namekata+, 2017)J/ApJS/229/30 : Revised stellar properties Q1-17 Kepler targets (Mathur+, 2017)J/ApJ/866/99 : Revised radii of KIC stars & planets, Gaia DR2 (Berger+, 2018)J/ApJS/235/38 : Kepler planetary cand. VIII. DR25 reliability (Thompson+, 2018)J/ApJS/241/29 : Flare catalog through LC data of Kepler DR25 (Yang+, 2019)J/AJ/158/109 : Occurrence rates of planets orbiting FGK stars (Hsu+, 2019)J/AJ/159/24 : Spectroscopy & Kepler data of the EB star V404 Lyr (Lee+, 2020)http://archive.stsci.edu/kepler/ : Kepler on MAST home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/871/187https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/871/187http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/871/187https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/871/187https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/871/187http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/871/187GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/871/187/table1 (Physical parameters of star spots and the host stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/871/187/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/871/187/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/871/187/table1?GETtext/xml+votable180.050000true281.025071447.28565310.0055555555555555566/14577 14581 14582 14584 14586 14734 14735 14744 14765 14770 14776 14778 14779 14816 14822 14825 14826 14828 14830 14921 14929 14939 14947 14962 15040 15041 15059 15106 15107 15112 15113 15120 15126 15127 15130 15132 15137 15139 15141 15148 15170 15178 15202https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/871/187?format=asciidefaultJ/ApJ/871/187/table1Physical parameters of star spots and the host starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/56] Sequential running number of the spot candidatesmeta.numberintKIC[2158548/12783364] Kepler Input Catalog identifier of the host starmeta.id;meta.mainintf_KIC[1/2]? Source flag on KIC (1)meta.codeintnullableTeff[5026/6000] Stellar effective temperature (2)Kphys.temperature.effectiveintlogg[4.28/4.69] Stellar surface gravity (2)log(cm.s**-2)phys.gravityfloatR*[0.7/2.7]? Corrected stellar radii (3)solRadphys.size.radiusfloatnullableProt[1/17] Stellar rotational perioddtime.periodfloatdT[13/351] Lifetimes of star spotsdtime.epochfloate_dT[0.6/104] Uncertainty in dTdstat.errorfloatAmax[1.6/68]? Maximum star spot area; in 10e+3MSH units (4)phys.areafloatnullablee_Amax[-12/-0.3]? Lower uncertainty for Amax (4)stat.errorfloatnullableE_Amax[0.4/15]? Upper uncertainty for Amax (4)stat.error;stat.maxfloatnullableImax[0.5/73]? Maximum magnetic flux ({Phi}_max_) in 10^23^Mx units (5)1e+23G.cm**2phys.magFieldfloatnullablee_Imax[-28/-0.2]? Lower uncertainty for Imax (5)1e+23G.cm**2stat.errorfloatnullableE_Imax[0.3/45]? Upper uncertainty for Imax (5)1e+23G.cm**2stat.error;stat.maxfloatnullabledI-e[0.3/87]? Emergence rates of star spots (d{Phi}_e_/dt) in 10^20^Mx/h units (5)1e+20G.cm**2.h**-1time;arith.ratiofloatnullablee_dI-e[-39/-0.1]? Lower uncertainty for dI-e (5)1e+20G.cm**2.h**-1stat.errorfloatnullableE_dI-e[0.2/68]? Upper uncertainty for dI-e (5)1e+20G.cm**2.h**-1stat.error;stat.maxfloatnullabledI-d[0.4/184]? decay rates of star spots (d{Phi}_d_/dt) in 10^20^Mx/h units (5)1e+20G.cm**2.h**-1time;arith.ratiofloatnullablee_dI-d[-74/-0.2]? Lower uncertainty for dI-d (5)1e+20G.cm**2.h**-1stat.errorfloatnullableE_dI-d[0.3/112]? Upper uncertainty for dI-d (5)1e+20G.cm**2.h**-1stat.error;stat.maxfloatnullableKCatDisplay the Kepler data from Berger+ 2018, J/ApJ/866/99 and Mathur+, 2017, J/ApJS/229/30meta.ref.urlcharSimbadSimbad column added by the CDSmeta.ref.urlchar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.main