J/A+A/645/L6ivo://CDS.VizieR/J/A+A/645/L6doi:10.26093/cds/vizier.36459006CDSFlores M.Jaque Arancibia M.Ibanez Bustos R.V.Buccino A.P.,Yana Galarza J.Nunez N.E.Miquelarena P.Alacoria J.Saffe C.,Mauas P.J.D.2021-09-06T08:33:57Z2021-01-11T09:10:32ZCDS support team

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

cds-question@unistra.frg-starsorbitsspectroscopyWe explore if the star zet02 Ret, which belongs to a binary system, is in (or going to) a state similar to the MM. To do so, we have collected more than 430 spectra acquired between 2000 and 2019 with the HARPS, REOSC, UVES, and FEROS spectrographs. We performed a detailed long-term activity study of both components using the Mount Wilson index, which is obtained from the Ca II H&K lines. To search for signs of an activity cycle, we analyzed the resulting time-series with the Generalized Lomb-Scargle and CLEAN periodograms. Our spectroscopic analysis shows a high activity level for zet01 Ret and a significant decrease in the magnetic activity cycle amplitude of zet02 Ret. By analogy with the scenario that proposes a weak solar cycle during the MM, we suggest that activity signatures showed by zet02 Ret, i.e., a very low activity level when compared to its stellar companion, a notably decreasing amplitude (~47%), and a cyclic behaviour, are possible evidence that this star could be in a MM state. It is, to our knowledge, the first MM candidate star detected through a highly discrepant activity behaviour in a binary system.2021A&A...645L...6Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/645/L6CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/588/A81 : Line list and abundances of the binary zet2 Ret (Saffe+, 2016)J/A+A/591/A34 : Chemical abundances of zeta Reticuly (Adibekyan+, 2016)J/A+A/614/A138 : HD 80606/80607 equivalent widths (Lui+, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/645/L6https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/645/L6http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/645/L6https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/645/L6https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/645/L6http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/645/L6GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapAssociated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/645/L6defaultJ/A+A/645/L6/table1Observational data and derived Mount Wilson indexes for zet01 Ret and zet02 RetrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsDate1? Observing date (zet 01 Ret)time.epochnullableJD1? Julian day (zet 01 Ret)dtime.epochfloatnullableInst1Instrument (zet 01 Ret)meta.id;instrcharObsProg1ID programs (zet 01 Ret)meta.id;obscharSMW1? Mount Wilson index (zet 01 Ret)phot.flux;arith.ratiofloatnullableObsDate2Observing date (zet 02 Ret)time.epochnullableJD2Julian day (zet 02 Ret)dtime.epochfloatInst2Instrument (zet 02 Ret)meta.id;instrcharObsProg2ID programs (zet 02 Ret)meta.id;obscharSMW2Mount Wilson index (zet 02 Ret)phot.flux;arith.ratiofloatJ/A+A/645/L6/listList of HD 20766 (zet01 Ret) spectraAssocDataAssociated Data web pagemeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNxNumber of pixels along X-axismeta.numberintObs.dateObservation datetime.epoch;obsnullableblambdaLower value of wavelength interval0.1nmem.wlfloatBlambdaUpper value of wavelength interval0.1nmem.wlfloatdlambdaWavelength resolution0.1nmspect.resolutiondoublesizeSize of FITS fileKibytephys.size;meta.fitsintspShow the spectrummeta.ref.urlcharFileNameName of FITS file, in subdirectory fitsmeta.id;meta.fitscharTitleTitle of the FITS filemeta.title;meta.fitschar