J/AJ/160/104ivo://CDS.VizieR/J/AJ/160/104doi:10.26093/cds/vizier.51600104CDSRucinski S.M.2021-09-22T07:32:01Z2020-11-05T13:35:10ZCDS support team

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

cds-question@unistra.frmultiple-starsvisible-astronomyspectroscopyradial-velocityHigh-resolution spectroscopic observations of the W UMa-type binary {Epsilon}CrA obtained as a time-monitoring sequence on four full and four partial nights within two weeks have been used to derive orbital elements of the system and discuss the validity of the Lucy model for description of the radial-velocity data. The observations had more extensive temporal coverage and better quality than similar time-sequence observations of the contact binary AW UMa. The two binaries share several physical properties and show very similar deviations from the Lucy model: the primary component is a rapidly rotating star almost unaffected by the presence of the secondary component, while the latter is embedded in a complex gas flow and appears to have its own rotation-velocity field, in contradiction to the model. The spectroscopic mass ratio is found to be larger than the one derived from the light-curve analysis, as in many other W UMa-type binaries, but the discrepancy for {Epsilon} CrA is relatively minor, much smaller than for AW UMa. The presence of the complex velocity flows contradicting the assumption of solid-body rotation suggests a necessity of modification to the Lucy model, possibly along the lines outlined by Stepien in his concept of energy transfer between the binary components.2020AJ....160..104Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/160/104CatalogResearchIsServedByTAP VizieR generic servicerelated-toI/345 : Gaia DR2 (Gaia Collaboration, 2018)J/AJ/132/161 : NStars project: The southern sample. I. (Gray+, 2006)J/A+A/450/681 : Companions to close spectroscopic binaries (Tokovinin+, 2006)J/AJ/131/1702 : Radial velocities for HD 27638B components (Torres+, 2006)J/AJ/134/2353 : Observations of contact binaries (Rucinski+, 2007)J/AJ/141/63 : Relative radial velocities of HAT-P-4 & HAT-P-14 (Winn+,2011)J/AJ/146/70 : Spectroscopy of W UMa-type binary stars (Rucinski+, 2013)J/AJ/149/49 : Radial velocities of AW UMa (Rucinski+, 2015)J/ApJ/806/60 : Radial velocities of 70 Vir (HD117176) (Kane+, 2015)J/MNRAS/457/836 : Eclipsing binaries MgI b and H{alpha} EW (Eaton, 2016)J/AJ/153/36 : Minima timings & RVs for 3 eclipsing binaries (Zasche+, 2017)J/A+A/624/A38 : Radial velocities of K2-36 (Damasso+, 2019)J/MNRAS/484/5362 : White dwarf+M dwarf binaries RVs (Ashley+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/160/104https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/160/104http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/160/104https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/160/104https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/160/104http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/160/104GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/160/104/table3The radial velocities of the primary component of {Epsilon} CrArecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJD[0.52/16.9] Heliocentric Julian Date at mid-exposure; HJD-2458312dtime.epochfloatOrb[0.76/28.4] Middle exposure time expressed as fraction of orbital periodmeta.notefloatV1[27.23/98.12] Centroid, rotational velocity fitting profilekm/sphys.veloc.rotatfloatvsini[140/167] Projected rotational velocity (1)km/sphys.veloc.rotatfloatKey[0/1] Used (1) or un-used (0) for primary-component analysismeta.codeintJ/AJ/160/104/table6Orbital velocities of the secondary component of {Epsilon} CrArecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintOrb[0.76/28.4] Middle exposure time expressed as fraction of binary orbital periodmeta.notefloatVel[-224/356] Radial velocity, secondary component (1)km/sspect.dopplerVelocfloat