J/ApJ/863/151ivo://CDS.VizieR/J/ApJ/863/151doi:10.26093/cds/vizier.18630151CDSLi L.-J.Qian S.-B.Zhu L.-Y.2020-04-28T13:28:31Z2019-09-18T08:37:20ZCDS support team

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

cds-question@unistra.frvariable-starsphotometryvisible-astronomyUsing the times of light maximum collected from the GEOS RR Lyrae database and determined from sky surveys, we utilize the O-C method to study the period variations of seven field ab-type RR Lyrae stars. The time coverage of data for most stars is more than 100 years, allowing us to investigate period changes over a large time span. We find that the O-C diagrams for most stars can be described by a combination of cyclic variations and long-term period changes. Assuming the former were caused by the light-travel-time effect, the pulsation and orbital parameters are obtained by the nonlinear fitting. We find that the orbital periods in our sample range from 33 to 78 years, and the eccentricities are relatively higher than the results for other candidates (e>0.6). The minimal masses of the potential companions of XX And, BK Dra, and RY Psc are less than one solar mass, and those of SV Eri, AR Her, and RU Scl are 3.3, 2.1, and 3.4M_{sun}_, respectively. Moreover, we suggest that the companion of AR Her may be a blue straggler that experienced mass transfer or a merger of two stars. The O-C diagram for ST Vir also shows distinct long- term period decrease, and in the O-C residuals, additional quasi-periodic variations that can be described by damped oscillation are found. Combining the data from the literature and our analysis, we plot the log P-AO-C diagram. The distribution of our binary candidates suggests that their period variations are not caused by the Blazhko effect.2018ApJ...863..151Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/863/151CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/vsx : AAVSO International Variable Star Index VSX (Watson+, 2006-2014)B/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)I/337 : Gaia DR1 (Gaia Collaboration, 2016)J/AJ/106/604 : Study of globular cluster NGC 6366 (Harris 1993)J/AJ/108/1786 : Blue stragglers & var. stars in M3 (Guhathakurta+, 1994)J/AJ/108/1016 : Kinematics of local RR lyrae stars. I. (Layden, 1994)J/A+AS/125/313 : RR Lyrae radial velocities and [Fe/H] I. (Fernley+ 1997)J/MNRAS/368/1757 : Catalogue of RR Lyrae from NSVS (Wils+, 2006)J/other/IBVS/5767 : GEOS RR Lyr survey (Le Borgne+, 2007)J/A+A/476/307 : Period variations in galactic RRab stars (Le Borgne+, 2007)J/MNRAS/377/1263 : Multiperiodic RR Lyrae in ASAS catalog (Szczygiel+, 2007)J/MNRAS/386/2115 : Type II Cepheid and RR Lyrae variables (Feast+, 2008)J/ApJ/696/870 : Catalina Real-time Transient Survey (CRTS) (Drake+, 2009)J/MNRAS/402/226 : NGC 5053 variables VrI light curves (Arellano Ferro+, 2010)J/AJ/139/2639 : DY Peg times of light maximum (Li+, 2010)J/A+A/548/A79 : INTEGRAL-OMC optically var. sources (Alfonso-Garzon+, 2012)J/AJ/144/39 : Gal. RRab stars from GEOS RR Lyr Survey (Le Borgne+, 2012)J/ApJS/213/31 : Blazhko effect from 4yr of Kepler data (Benko+, 2014)J/other/IBVS/6106 : RR Lyrae stars in GCVS observed by the QES (Bramich+, 2014)J/A+A/562/A90 : Times of maximum light of Blazhko RRab stars (Skarka, 2014)J/AcA/64/177 : VI LCs of Galactic Bulge RR Lyrae (Soszynski+, 2014)J/A+A/589/A94 : TU UMa light curves & maxima, CL Aur minima (Liska+, 2016)J/MNRAS/459/4360 : Field RR Lyrae stars (Liska+, 2016)J/MNRAS/456/2070 : Eccentricity distribution of wide bin. (Tokovinin+, 2016)J/AJ/154/263 : NIR photometry of 77 RR Lyrae stars (Karczmarek+, 2017)http://rr-lyr.irap.omp.eu/dbrr/ : GEOS RR Lyr databasehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/863/151https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/863/151http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/863/151https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/863/151https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/863/151http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/863/151GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/863/151/rrab (The 7 RRab star sample, and pulsation and orbital parameters for six of them (Tables 1 and 5))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/863/151/rrab?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/863/151/rrab?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/863/151/rrab?GETtext/xml+votable180.050000true19.36416738.9505560.0055555555555555566/2629 9938 16022 16602 18080 25953 36704https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/863/151?format=asciiOpticaldefaultJ/ApJ/863/151/rrabThe 7 RRab star sample, and pulsation and orbital parameters for six of them (Tables 1 and 5)a1sini[4.7/14.8]? a_1_sini (3)auphys.size.radiusfloatnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNtgNumber of times of light maximum from GEOS (link to Table 2)meta.numberintnullableNtsNumber of times of light maximum from sky surveys (link to Table 4)meta.numberintnullableNameStar namemeta.id;meta.maincharprimaryf_NameFlag on name (1)meta.codecharRAJ2000Hour of right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of declination (J2000)pos.eq.dec;meta.mainVmagLoLower range of V-band magnitude from B/vsxphot.mag;em.opt.V;stat.minfloatVmagUpUpper range of V-band magnitude from B/vsxphot.mag;em.opt.V;stat.maxfloatT0Heliocentric Julian Datedtime.epochdoublePpul[0.4/0.8] Pulsation perioddtime.perioddouble[Fe/H][-2.2/-0.8] Abundance [Fe/H]log(Sun)phys.abund.Fefloatr_[Fe/H][1/2] [Fe/H] referencemeta.refintM1[0.5/0.7] Star mass (2)solMassphys.massfloatCov[85/120] Span of the times of light maximumyrtime.intervalintDatesDate coveragetime.epochcharPpulc[0.4/0.8]? Corrected pulsation perioddtime.perioddoublenullablee_Ppulc[4e-8/6e-7]? Ppul uncertaintydstat.errordoublenullableT0c[25523/42682]? Corrected epoch; JD-2400000dtime.epochdoublenullablee_T0c[0.001/0.02]? T0 uncertaintydstat.errorfloatnullablebeta[-0.4/1.9]? Linear changes of pulsation period in day Myr^-1^meta.notefloatnullablee_beta[0.006/0.03]? beta uncertaintystat.errorfloatnullableA[0.02/0.09]? a_1_sini/c in light days (3)phys.size.radiusfloatnullablee_A[0.002/0.03]? A uncertaintystat.errorfloatnullablee_a1sini[0.2/5]? a1sini uncertaintyaustat.errorfloatnullablee[0.6/0.9]? Orbital eccentricitysrc.orbital.eccentricityfloatnullablee_e? e uncertaintystat.errorfloatnullablef_ef: fixedmeta.codecharomega[43/341]? Longitude of the periastron passage in the plane of the orbitdegsrc.orbital.periastronintnullablee_omega[4/13]? omega uncertaintydegstat.errorintnullablePorb[33.1/78.4]? Orbital period of the binary systemyrtime.periodfloatnullablee_Porb[0.3/1.8]? Porb uncertaintyyrstat.errorfloatnullableT[21113/43717]? Time of passage through the periastrondtime.epochintnullablee_T[207/672]? T uncertaintydstat.errorintnullablefm[0.02/2.6]? Mass function of companionsolMassphys.massfloatnullablee_fm[0.04/2.2]? fm uncertaintysolMassstat.errorfloatnullableK1[3/22.7]? Semi-amplitude velocitykm/sphys.velocfloatnullablee_K1[0.4/9.1]? K1 uncertaintykm/sstat.errorfloatnullabledPpul[1.5/9.4]? Range of the pulsation period ({Delta}P_pul_)dtime.periodfloatnullablee_dPpul[0.1/3]? dPpul uncertaintydstat.errorfloatnullableSimbadSimbad column added by the CDSmeta.ref.urlcharJ/ApJ/863/151/table4The times of light maximum of the seven RRab stars determined from the sky surveysrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharHJDmaxMaximum Heliocentric Julian Date; JD-2400000dtime.epochdoublee_HJDmax[0.0001/0.08] Error in HJD-Maxdstat.errorfloatRefReference (1)meta.ref;pos.framecharJ/ApJ/863/151/table2Times of light maximum of the seven RRab stars obtained from GEOS databaserecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameStar namemeta.id;meta.maincharHJDmaxMaximum Heliocentric Julian Date (1)dtime.epochdoublee_HJDmax[0.0002/0.05]? Error in HJD-Maxdstat.errorfloatnullableMethMethod (2)meta.notecharRefReferencemeta.ref;pos.framechar