J/MNRAS/435/707ivo://CDS.VizieR/J/MNRAS/435/707doi:10.26093/cds/vizier.74350707CDSArmstrong E.Patterson J.Michelsen E.Thorstensen J.Uthas H.,Vanmunster T.Hambsch F.-J.Roberts G.Dvorak S.2024-08-06T20:17:24Z2015-03-05T07:21:28ZCDS support team

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

cds-question@unistra.frcataclysmic-variable-starsradial-velocityWe report photometric detections of orbital and superorbital signals, and negative orbital sidebands, in the light curves of the nova-like cataclysmic variables AQ Mensae and IM Eridani. The frequencies of the orbital, superorbital and sideband signals are 7.0686 (3), 0.263 (3) and 7.332 (3) cycles/d (c/d) in AQ Mensae, and 6.870 (1), 0.354 (7) and 7.226 (1) c/d in IM Eridani. We also find a spectroscopic orbital frequency in IM Eridani of 6.86649 (2) c/d. These observations can be reproduced by invoking an accretion disc that is tilted with respect to the orbital plane. This model works well for X-ray binaries, in which irradiation by a primary neutron star can account for the disc's tilt. A likely tilt mechanism has yet to be identified in CVs, yet the growing collection of observational evidence indicates that the phenomenon of tilt is indeed at work in this class of object. The results presented in this paper bring the number of CVs known to display signals associated with retrograde disc precession to 12. We also find AQ Men to be an eclipsing system. The eclipse depths are highly variable, which suggests that the eclipses are grazing. This finding raises the possibility of probing variations in disc tilt by studying systematic variations in the eclipse profile.2013MNRAS.435..707Ahttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/435/707CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/435/707https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/435/707http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/435/707https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/435/707https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/435/707http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/435/707GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/MNRAS/435/707/table3Spectroscopy of IM EridanirecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintObsDateObservation datetime.epoch;obsnullableNframeNumber of frames per eveningmeta.numberintHAStartHour angle of starting observationpos.eq.ha;obsnullableHAEndHour angle of ending observationpos.eq.ha;obsnullableTel[1.3/2.4] Telescope sizeminstr.telfloatJ/MNRAS/435/707/table4IM Eri: H-alpha radial velocitiesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintBJDBarycentric Julian date (BJD-2400000)dtime.epochdoubleRVH{alpha} radial velocitykm/sphys.veloc;pos.heliocentricinte_RVH{alpha} velocity dispersionkm/sstat.errorint