J/AJ/109/359ivo://CDS.VizieR/J/AJ/109/359doi:10.26093/cds/vizier.51090359CDSMilone E.F.Stagg C.R.Sugars B.A.McVean J.R.Schiller S.J.,Kallrath D. H. Bradstreet J.2023-04-06T16:50:11Z1997-12-09T20:25:24ZCDS support team

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

cds-question@unistra.fropen-star-clustersvariable-starsphotometryThe short-period variable star Heinemann 235 in the open cluster NGC 752 has been identified as a contact binary with a variable period of about 0.4118 d. BVRI light curves and radial velocity curves have been obtained and analyzed with enhanced versions of the Wilson-Devinney light curve program. We find that the system is best modeled as an A-type W UMa system, with a contact parameter of 0.21 +/- 0.11. The masses of the components are found to be 1.18 +/- 0.17 and 0.24 +/- 0.04 Msun, with bolometric magnitudes of 3.60 +/- 0.10 and 5.21 +/- 0.13, for the hotter (6500 K, assumed) and cooler (6421 K) components, respectively, with Delta T = 79 +/- 25 K. The distance to the binary is established at 381 +/- 17 pc. H235 becomes one of a relatively small number of open-cluster contact systems with detailed light curve analysis for which an age may be estimated. If it is coeval with the cluster, and with the detached eclipsing and double-lined spectroscopic binary H219 (DS And), H235 is ~1.8 Gyr old, and may provide a fiducial point for the evolution of contact systems. There is, however, evidence for dynamical evolution of the cluster and the likelihood of weak interactions over the age of the binary precludes the determination of its initial state with certainty.1995AJ....109..359Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/109/359CatalogResearchIsServedByTAP VizieR generic servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/109/359https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/109/359http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/109/359https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/109/359https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/109/359http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/109/359GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticaldefaultJ/AJ/109/359/table3Photoelectric light curve datarecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJDHeliocentric Julian Datedtime.epochdoublePh1*[0/1[ Phase of minima from ephemeris 1time.phasefloatPh3*[0/1[ Phase of minima from ephemeris 3time.phasefloatdVmagDifferential V magnitudemagphot.mag;arith.difffloatdBmagDifferential B magnitudemagphot.mag;arith.difffloatdRmagDifferential R magnitudemagphot.mag;arith.difffloatdImagDifferential I magnitudemagphot.mag;arith.difffloatd(B-V)Differential (B-V) colormagphot.color;arith.difffloatd(V-R)Differential (V-R) colormagphot.color;arith.difffloatd(V-I)?Differential (V-I) colormagphot.color;arith.difffloat