J/MNRAS/467/1830ivo://CDS.VizieR/J/MNRAS/467/1830doi:10.26093/cds/vizier.74671830CDSBalona L.A.2024-08-17T20:18:12Z2019-12-16T09:22:21ZCDS support team

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

cds-question@unistra.fra-starsvariable-starsRotation modulation of Kepler light curves in mid-A to late-B stars is shown to be present. This is demonstrated by the high correlation of projected rotational velocities with photometric frequencies in 30 stars. The time-frequency diagrams show stochastic variations in all respects similar to those in spotted cool stars. This disposes of any explanation in terms of binary proximity effects. More than half of the sample of stars with effective temperatures in the range of 8300-12000K show rotational modulation, indicating that starspots are the rule rather than the exception among A stars. The periodograms of a subset of these stars show a characteristic pattern in which a broad peak is flanked by a sharp peak at a slightly higher frequency. It is demonstrated that the sharp peak has the same width as the spectral window, indicating a stable period over the duration of the 4-yr Kepler observations. It is speculated that this might be a signature of a reflection effect in a non-transiting planet. These observations suggest that the presence of localized magnetic fields in A and B stars and that current views of radiative stellar envelopes need to be revised.2017MNRAS.467.1830Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/467/1830CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/133 : Kepler Input Catalog (Kepler Mission Team, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/467/1830https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/467/1830http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/467/1830https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/467/1830https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/467/1830http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/467/1830GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/467/1830/table1 (Results described above)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/467/1830/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/467/1830/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/467/1830/table1?GETtext/xml+votable180.050000true291.4853836.74499890.0055555555555555565/3645-3646 3683 3688-3689 3691-3692 3694-3695 3704 3706 3732-3733 3741 3776-3777 3779-3780 3782 3784-3785 3792 6/14559 14567 14573 14575 14578-14579 14588-14589 14591 14730-14731 14738 14744 14746 14749-14751 14761-14763 14772-14774 14792 14794-14795 14822 14828 14830 14917-14918 14920-14921 14924-14926 14936-14938 14940-14942 14946 14948 14950-14951 14956 14959-14960 14962-14963 14969 14972 14974-14975 15041 15044 15057 15112-15113 15115 15124-15126 15132-15133 15135 15144-15146 15148-15150 15153 15155 15157-15160 15172-15174 15176 15200 15232https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/467/1830?format=asciidefaultJ/MNRAS/467/1830/table1Results described aboveKICKepler numbermeta.id;meta.mainintAmp? Amplitude (3)(10-6)src.var.amplitudeintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintVTypeVariability type (1)meta.notecharKpKepler magnitude (2)magphot.mag;em.optfloatTeffEffective Temperature (2)Kphys.temperature.effectiveintlogg? Surface gravity (2)log(cm.s**-2)phys.gravityfloatnullableFreq? Rotational frequency (3)d**-1phys.veloc.rotatfloatnullableDelFreq? Frequency spread (3)d**-1phys.velocfloatnullableSimbadSimbad column added by the CDSmeta.ref.urlchar_RAPositions from KIC catalog (right ascension part)degpos.eq.ra;meta.main_DEPositions from KIC catalog (declination part)degpos.eq.dec;meta.main