J/AJ/169/82ivo://CDS.VizieR/J/AJ/169/82doi:10.26093/cds/vizier/be-59-2jCDSRucinski S.M.2026-07-02T11:52:26Z2025-11-21T10:43:07ZCDS support team

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

cds-question@unistra.frradial-velocitymultiple-starsspectroscopyvisible-astronomyA re-examination of high-resolution spectral monitoring of the W UMa-type binaries AW UMa and {epsilon} CrA casts doubt on the widely utilized L. B. Lucy model of contact binaries. The detection of the very faint profile of the secondary component in AW UMa leads to a new spectroscopic determination of the mass ratio, q_sp_=0.092+/-0.007, which is close to the previous, medium-resolution spectroscopic result of T. Pribulla & S. M. Rucinski, q_sp_=0.101+/-0.006, and remains substantially different from a cluster of generally accepted photometric results by several authors, concentrated around q_ph_=0.080+/-0.005. A survey of binaries with the best-determined values of the mass ratio shows a common tendency for q_ph_<q_sp_. The tendency for systematically smaller values of q_ph_ may result from the overfilling of the primary lobe and underfilling of the secondary lobe relative to the Roche model geometry, as predicted by the K. Stepien model. Despite the observed moderate inter-systemic velocities, the photometric Lucy model may remain useful in providing approximate, though biased, results for the mass ratio. A complicating factor in detailed spectral analysis may be the occurrence of Enhanced Spectral-line Perturbations (ESPs) projected over the secondary profiles, appearing in different numbers in the two studied binaries. The ESPs are tentatively identified within the Stepien model as collision fronts or fountains of primary-component gas from the circumbinary, energy-carrying flow.2025AJ....169...82Rhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/169/82CatalogResearchIsServedByTAP VizieR generic servicerelated-toI/350 : Gaia EDR3 (Gaia Collaboration, 2020)J/AJ/130/767 : Radial velocity studies of close binary stars (Rucinski+, 2005)J/ApJ/629/1055 : Evolution of close binary systems (Yakut+, 2005)J/AJ/132/769 : Radial velocities of 10 close binaries (Pribulla+, 2006)J/AJ/132/1539 : Radial velocities of southern close binaries (Rucinski+, 2006)J/A+A/450/681 : Companions to close spectroscopic binaries (Tokovinin+, 2006)J/AJ/133/1977 : Radial velocities of 10 close binaries (Pribulla+, 2007)J/AJ/134/2353 : Observations of contact binaries (Rucinski+, 2007)J/AJ/136/586 : Radial velocities of 10 close binaries (Rucinski+, 2008)J/AJ/137/3655 : Radial velocities of 8 close binaries (Pribulla+, 2009)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/AcA/65/39 : OGLE Gal. Bulge ultra-short-period binaries (Soszynski+, 2015)J/AJ/160/104 : {Epsilon} CrA components radial & orbit. veloc. (Rucinski, 2020)J/ApJS/254/10 : Compilation of W UMa stars (Latkovic+, 2021)J/AJ/164/202 : Extremely Low Mass Ratio Contact Binaries I. 10 syst. (Li+,2022)J/A+A/672/A176 : Mass-ratio distribution of contact binary stars (Pesta+, 2023)J/A+A/687/A259 : Altair light curves (Rieutord+, 2024)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/169/82https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/169/82http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/169/82https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/169/82https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/169/82http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/169/82GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/169/82/table1AW UMa: Radial velocities of the secondary-component profile edgesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintPhase[0.6/5.7] Orbital phase (1)time.phasefloatRVel1[-409/212.1] Secondary component profile's first edge heliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloatRVel2[-260/401.7] Secondary component profile's second edge heliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricfloat