J/AJ/156/199ivo://CDS.VizieR/J/AJ/156/199doi:10.26093/cds/vizier.51560199CDSSarotsakulchai T.Qian S.-B.Soonthornthum B.Zhou X.Zhang J.,Reichart D.E.Haislip J.B.Kouprianov V.V.Poshyachinda S.2019-04-08T14:22:56Z2019-04-02T07:50:56ZCDS support team

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

cds-question@unistra.freclipsing-binary-starsinfrared-photometryvisible-astronomybroad-band-photometryTY Pup is a well-known bright eclipsing binary with an orbital period of 0.8192 days. New light curves in B, V, (RI)_C_ bands were obtained with the 0.61 m reflector robotic telescope (PROMPT-8) at CTIO in Chile during 2015 and 2017. By analyzing those photometric data with the W-D method, it is found that TY Pup is a low-mass-ratio (q~0.184) and deep-contact binary with a high fill-out factor (84.3%). An investigation of all available times of minimum light including three new ones obtained with the 60 cm and the 1.0 m telescopes at Yunnan Observatories in China indicates that the period change of TY Pup is complex. An upward parabolic variation in the O-C diagram is detected to be superimposed on a cyclic oscillation. The upward parabolic change reveals a long-term continuous increase in the orbital period at a rate of dP/dt=5.57(+/-0.08)x10^-8^ days/yr. The period increase can be explained by mass transfer from the less massive component (M_2_~0.3 M_{sun}_) to the more massive one (M_1_~1.65 M_{sun}_). The binary will be merging when it meets the criterion that the orbital angular momentum is less than three times the total spin angular momentum, i.e., J_orb_<3J_rot_. This suggests that the system will finally merge into a rapid-rotating single star and may produce a luminous red nova. The cyclic oscillation in the O-C diagram can be interpreted by the light-travel time effect via the presence of a third body.2018AJ....156..199Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/156/199CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/311/523 : Photometry of W UMa (Maceroni+, 1996)J/MNRAS/357/497 : Kinematics of W UMa-type binaries (Bilir+, 2005)J/AJ/134/2353 : Observations of contact binaries (Rucinski+, 2007)J/MNRAS/412/1787 : Physical parameters of 62 eclipsing binariesJ/AJ/143/99 : Photometry of W UMa eclipsing binaries (Terrell+, 2012)J/AJ/146/70 : Spectroscopy of W UMa-type binary starsJ/other/RMxAA/53.235 : Photometry of 6 deep-contact W UMa (Kjurkchieva+, 2017)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/156/199https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/156/199http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/156/199https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/156/199https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/156/199http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/156/199GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapOpticalInfrareddefaultJ/AJ/156/199/table2CCD observations in BVRI bands for TY Pup observed in 2015recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJD-B[33.6422/51.6432] Heliocentric observation date of B band (HJD-2457000)dtime.epochfloatDBmag[0.158/0.642] B band magnitude difference between variable and comparison (HD 60342) starsmagphot.mag;em.opt.B;arith.difffloatHJD-V[33.6425/52.515] Heliocentric observation date of V band (HJD-2457000)dtime.epochfloatDVmag[-0.286/0.213] V band magnitude difference between variable and comparison (HD 60342) starsmagphot.mag;em.opt.V;arith.difffloatHJD-R[33.6427/51.6504] Heliocentric observation date of R_C_ band (HJD-2457000)dtime.epochfloatDRmag[-0.537/-0.061] R_C_ band magnitude difference between variable and comparison (HD 60342) starsmagphot.mag;em.opt.R;arith.difffloatHJD-I[33.643/52.5376] Heliocentric observation date of I_C_ band (HJD-2457000)dtime.epochfloatDImag[-0.77/-0.298] I_C_ band magnitude difference between variable and comparison (HD 60342) starsmagphot.mag;em.opt.I;arith.difffloatJ/AJ/156/199/table3CCD observations in BVRI bands for TY Pup observed in 2017recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHJD-B[33.6422/51.6432] Heliocentric observation date of B band (HJD-2457000)dtime.epochfloatDBmag[0.158/0.642] B band magnitude difference between variable and comparison (HD 60342) starsmagphot.mag;em.opt.B;arith.difffloatHJD-V[33.6425/52.515] Heliocentric observation date of V band (HJD-2457000)dtime.epochfloatDVmag[-0.286/0.213] V band magnitude difference between variable and comparison (HD 60342) starsmagphot.mag;em.opt.V;arith.difffloatHJD-R[33.6427/51.6504] Heliocentric observation date of R_C_ band (HJD-2457000)dtime.epochfloatDRmag[-0.537/-0.061] R_C_ band magnitude difference between variable and comparison (HD 60342) starsmagphot.mag;em.opt.R;arith.difffloatHJD-I[33.643/52.5376] Heliocentric observation date of I_C_ band (HJD-2457000)dtime.epochfloatDImag[-0.77/-0.298] I_C_ band magnitude difference between variable and comparison (HD 60342) starsmagphot.mag;em.opt.I;arith.difffloat