J/A+A/544/A53ivo://CDS.VizieR/J/A+A/544/A53doi:10.26093/cds/vizier.35440053CDSGalan C.Mikolajewski M.Tomov T.Graczyk D.Apostolovska G.,Barzova I.Bellas-Velidis I.Bilkina B.Blake R.M.Bolton C.T.,Bondar A.Brat L.Brozek T.Budzisz B.Cikala M.Csak B.,Dapergolas A.Dimitrov D.Dobierski P.Drahus M.Drozdz M.Dvorak S.,Elder L.Frackowiak S.Galazutdinov G.Gazeas K.Georgiev L.Gere B.,Gozdziewski K.Grinin V.P.Gromadzki M.Hajduk M.Heras T.A.,Hopkins J.Iliev I.Janowski J.Kocian R.Kolaczkowski Z.Kolev D.,Kopacki G.Krzesinski J.Kucakova H.Kuligowska E.Kundera T.,Kurpinska-Winiarska M.Kuzmicz A.Liakos A.Lister T.A.Maciejewski G.,Majcher A.Majewska A.Marrese P.M.Michalska G.Migaszewski C.,Miller I.Munari U.Musaev F.Myers G.Narwid A.Nemeth P.,Niarchos P.Niemczura E.Ogloza W.Oegmen Y.Oksanen A.Osiwala J.,Peneva S.Pigulski A.Popov V.Pych W.Pye J.Ragan E.Roukema B.F.,Rozanski P.T.Semkov E.Siwak M.Staels B.Stateva I.Stempels H.C.,Steslicki M.Swierczynski E.Szymanski T.Tomov N.Waniak W.,Wiecek M.Winiarski M.Wychudzki P.Zajczyk A.Zola S.Zwitter T.2023-02-09T16:31:42Z2012-10-04T09:23:48ZCDS support team

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

cds-question@unistra.freclipsing-binary-starsinfrared-photometryvisible-astronomybroad-band-photometryEE Cep is an unusual long-period (5.6yr) eclipsing binary discovered during the mid-twentieth century. It undergoes almost-grey eclipses that vary in terms of both depth and duration at different epochs. The system consists of a Be type star and a dark dusty disk around an invisible companion. EE Cep together with the widely studied epsilon Aur are the only two known cases of long-period eclipsing binaries with a dark, dusty disk component responsible for periodic obscurations. Two observational campaigns were carried out during the eclipses of EE Cep in 2003 and 2008/9 to verify whether the eclipsing body in the system is indeed a dark disk and to understand the observed changes in the depths and durations of the eclipses. Multicolour photometric data and spectroscopic observations performed at both low and high resolutions were collected with several dozen instruments located in Europe and North America. We numerically modelled the variations in brightness and colour during the eclipses. We tested models with different disk structure, taking into consideration the inhomogeneous surface brightness of the Be star. We considered the possibility of disk precession. The complete set of observational data collected during the last three eclipses are made available to the astronomical community. The 2003 and 2008/9 eclipses of EE Cep were very shallow. The latter is the shallowest among all observed. The very high quality photometric data illustrate in detail the colour evolution during the eclipses for the first time. Two blue maxima in the colour indices were detected during these two eclipses, one before and one after the photometric minimum. The first (stronger) blue maximum is simultaneous with a "bump" that is very clear in all the UBV(RI)C light curves. A temporary increase in the I-band brightness at the orbital phase ~0.2 was observed after each of the last three eclipses. Variations in the spectral line profiles seem to be recurrent during each cycle. The NaI lines always show at least three absorption components during the eclipse minimum and strong absorption is superimposed on the H{alpha} emission. These observations confirm that the eclipsing object in EE Cep system is indeed a dark, dusty disk around a low luminosity object. The primary appears to be a rapidly rotating Be star that is strongly darkened at the equator and brightened at the poles. Some of the conclusions of this work require verification in future studies: (i) a complex, possibly multi-ring structure of the disk in EE Cep; (ii) our explanation of the "bump" observed during the last two eclipses in terms of the different times of obscuration of the hot polar regions of the Be star by the disk; and (iii) our suggested period of the disk precession (~11-12Porb) and predicted depth of about 2m for the forthcoming eclipse in 2014.2012A&A...544A..53Ghttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/544/A53CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/544/A53https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/544/A53http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/544/A53https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/544/A53https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/544/A53http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/544/A53GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapAssociated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/A+A/544/A532.367228618189496e-19 6.118840631666147e-19OpticalInfrareddefaultJ/A+A/544/A53/tableb35*The mean points of the average UBV(RI)c light curves obtained during and near the 2003 (E=9) and 2008/9 (E=10) eclipses.recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJDU? Julian date of observation for U banddtime.epochdoublenullableUmag? U-band photometry (1)magphot.mag;em.opt.Ufloatnullablee_Umag? rms uncertainty on Umagmagstat.error;phot.magfloatnullableo_Umag? The number of averaged photometric pointsmeta.numberintnullableJDB? Julian date of observation for B banddtime.epochdoublenullableBmag? B-band photometry (1)magphot.mag;em.opt.Bfloatnullablee_Bmag? rms uncertainty on Bmagmagstat.error;phot.magfloatnullableo_Bmag? The number of averaged photometric pointsmeta.numberintnullableJDV? Julian date of observation for V banddtime.epochdoublenullableVmag? V-band photometry (1)magphot.mag;em.opt.Vfloatnullablee_Vmag? rms uncertainty on Vmagmagstat.error;phot.magfloatnullableo_Vmag? The number of averaged photometric pointsmeta.numberintnullableJDRc? Julian date of observation for Rc banddtime.epochdoublenullableRcmag? Rc-band photometry (1)magphot.mag;em.opt.Rfloatnullablee_Rcmag? rms uncertainty on Rcmagmagstat.error;phot.magfloatnullableo_Rcmag? The number of averaged photometric pointsmeta.numberintnullableJDIc? Julian date of observation for Ic banddtime.epochdoublenullableIcmag? Ic-band photometry (1)magphot.mag;em.opt.Ifloatnullablee_Icmag? rms uncertainty on Icmagmagstat.error;phot.magfloatnullableo_Icmag? The number of averaged photometric pointsmeta.numberintnullableJ/A+A/544/A53/tableb36List of spectra obtained during and near of the last three eclipses of EE Cep (from E=8 to E=10) and names of the corresponding FITS filesRResolving powerspect.resolutionintspspectrummeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsDate of observationstime.epochnullableHJDHeliocentric Julian datedtime.epochdoublePhasePhase according to Mikolajewski & Graczyk (1999MNRAS.303..521M) ephemeristime.phasedoubleObsNameName of observatorymeta.id;instr.obstycharInstTelescope and instrumentinstrcharlambdaSpectral rangeinstr.bandwidthcharFileNameThe name of FITS file in subdirectory sp, spectra from Piwnice Observatory will be added latermeta.id;meta.fitscharJ/A+A/544/A53/photomBV(RI)c photometry, EE Cep eclipse 2008/9, Sonoita Res. Obs., 0.5m Cassegrain telescopee_dmag? rms uncertainty on dmagmagstat.error;phot.magfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsNoObservation code (B22 or B23), in notes.dat filemeta.code;obscharn_Date[HJD or JD]meta.notecharDateJulian date of observation (JD or HJD)dtime.epoch;obsdoublemagMagnitude in Bandmagphot.magfloatdmagDifferential magnitude in Band (1)magphot.mag;arith.difffloatBand[BVRcIc ] Observed bandinstr.bandpasscharJ/A+A/544/A53/photom1EE Cep eclipses differential photometry (1 comparison star)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsNoObservation code, in notes.dat filemeta.code;obscharn_Date[HJD or JD]meta.notecharDateJulian date of observation (JD or HJD)dtime.epoch;obsdoubledmagDifferential magnitude (1)magphot.mag;arith.difffloate_dmag? rms uncertainty on dmag (only for B1, B6 and B12)magstat.error;phot.magfloatnullableBand[UBVRIci Hb Han Haw] Observed band (2)instr.bandpasscharJ/A+A/544/A53/photom3EE Cep eclipses differential photometry (3 comparison stars)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsNoObservation code, in notes.dat filemeta.code;obscharn_Date[HJD or JD]meta.notecharDateJulian date of observation (JD or HJD)dtime.epoch;obsdoubledmaga? Differential B-band photometry, v-a (1)magphot.mag;arith.difffloatnullabledmagb? Differential B-band photometry, v-b (2)magphot.mag;arith.difffloatnullabledmagcDifferential B-band photometry, v-c (3)magphot.mag;arith.difffloatBand[UBV RcIc] Observed bandinstr.bandpasscharJ/A+A/544/A53/notesObservation informationsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsNoObservation codemeta.code;obscharprimaryComInformation on observationmeta.notechar