J/PASP/134/K4202ivo://CDS.VizieR/J/PASP/134/K4202doi:10.26093/cds/vizier.61353202CDSGao X.-Y.Li K.Cai Y.-W.Guo Y.-N.Gao X.Wang X.Yin S.-P.Liu F.,Sun G.-Y.2025-09-09T14:15:17Z2023-05-05T13:32:54ZCDS support team

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

cds-question@unistra.freclipsing-binary-starsinfrared-photometryvisible-astronomybroad-band-photometryPhotometric analysis and spectroscopic study of the long-period low-mass-ratio deep-contact binary KN Per were performed. The light curves of the BV(RI)_c_ band were from the Ningbo Bureau of Education and Xinjiang Observatory Telescope at the Xingming Observatory. Through the analysis of the Wilson-Devinney program, KN Per was found as an A-type low-mass-ratio deep-contact binary (q=0.236; f=53.4%). A cool spot applied on the primary component was introduced to explain the unequal maxima of the light curve. Based on the O-C analysis, we found that the rate of the increasing orbital period is dP/dt=5.12+/-(0.30)x10^-7^day/yr, meaning the mass transfer from the secondary component to the primary one. By analyzing the spectroscopic data, we detected chromospheric activity emission line indicators, which correspond to the light-curve analysis. Seventy-one long-period (P>0.5 day) contact binaries, including our target, were collected. The evolutionary states of all collected stars were investigated by the illustrations of mass-radius, mass-luminosity, and log M_T_-logJ_o_. The relations of some physical parameters were also determined. With the instability parameters of KN Per, we determined that it is a stable contact binary system at present.2022PASP..134k4202Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/PASP/134/K4202CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/PASP/134/K4202https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/PASP/134/K4202http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/PASP/134/K4202https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/PASP/134/K4202https://vizier.iucaa.in/viz-bin/votable?-source=J/PASP/134/K4202http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/PASP/134/K4202GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/PASP/134/K4202/table3Photometric data of KN Per obtained on 2019 November 14, 16, 17, 19, and 20recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDBB-band HJD (HJD-2400000)dtime.epochdoubleDBmagDifferential B magnitudemagphot.mag;arith.difffloatHJDV? V-band HJD (HJD-2400000)dtime.epochdoublenullableDVmag? Differential V magnitudemagphot.mag;arith.difffloatnullableHJDRc? Rc-band HJD (HJD-2400000)dtime.epochdoublenullableDRcmag? Differential Rc magnitudemagphot.mag;arith.difffloatnullableHJDIc? Ic-band HJD (HJD-2400000)dtime.epochdoublenullableDIcmag? Differential Ic magnitudemagphot.mag;arith.difffloatnullableJ/PASP/134/K4202/table6Minimum timings of KN PerrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDBJD (BJD-2400000)dtime.epochdoublee_BJD? Error on BJDdstat.errordoublenullableEEpochtime.epochfloatO-CObserved minus computedstat.fit.residualdoubleResResidualstat.fit.residualdoubleRefReference (1)meta.ref;pos.frameint