J/ApJS/281/38ivo://CDS.VizieR/J/ApJS/281/38CDSZhang J.Chen X.Wang S.Wang J.Deng L.2026-08-10T09:15:00Z2026-08-10T10:02:38ZCDS support team

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

cds-question@unistra.frvariable-starssurveysvisible-astronomyphotometryRR Lyrae (RRL) variable stars are cornerstone distance indicators. In particular, double-mode RR Lyrae (RRd) stars enable period-luminosity relations (PLRs) that are less sensitive to metallicity, reducing systematic biases in distance measurements. However, their utility has been limited by a global sample of only ~3000 objects. We develop an automated RRd-screening pipeline and apply it to a crossmatched sample between the Gaia DR3 RRL catalog and Zwicky Transient Facility (ZTF) DR22 time-series photometry. The workflow combines Lomb-Scargle period searches, iterative prewhitening, period-ratio constraints that suppress ~1 day sampling aliases, and amplitude-based quality cuts, enabling large-scale RRd star screening. We produce two ZTF-based catalogs: (i) 39,322 reliable single-mode RRL stars (40.5% of the crossmatched set) and (ii) 969 RRd stars. Among the RRd stars, 614 objects are newly identified, substantially enlarging this previously scarce sample; the catalog achieves an estimated completeness of 47.7%. The PLR derived from the newly discovered RRd stars agrees with the LMC-based relation, though with larger uncertainties. Incorporating these stars will help tighten the RRd PLR and improve distance measurements. Looking ahead, systematic RRd searches with upcoming surveys such as the Legacy Survey of Space and Time and the China Space Station Telescope should further extend high-accuracy distances across the Local Group and strengthen their cosmological applications.2025ApJS..281...38Zhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/281/38CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/366 : ASAS-SN catalog of variable stars (Jayasinghe+, 2018-2020)I/355 : Gaia DR3 Part 1. Main source (Gaia Collaboration, 2022)I/358 : Gaia DR3 Part 4. Variability (Gaia Collaboration, 2022)J/AcA/64/177 : VI light curves of Gal. Bulge RR Lyrae (Soszynski+, 2014)J/ApJS/219/25 : LCs of RR Lyrae stars in M3 (NGC5272) (Jurcsik+, 2015)J/ApJ/807/127 : Properties of 70 RR Lyrae stars in LMC bar (Muraveva+, 2015)J/MNRAS/487/5584 : First-overtone RR Lyrae stars from OGLE (Netzel+, 2019)J/A+A/625/A14 : Reclassification of Cepheids in the Gaia DR2 (Ripepi+, 2019)J/AcA/69/321 : OGLE RR Lyrae stars in Gal. bulge & disk (Soszynski+, 2019)J/ApJS/249/18 : The ZTF catalog of periodic variable stars (Chen+, 2020)J/MNRAS/513/1958 : Study of RR Lyrae stars in MW substructures (Wang+, 2022)J/other/NatAs/7.1081 : Double-mode RR Lyrae stars data (Chen+, 2023)J/A+A/674/A18 : Gaia DR3. The RR Lyrae sample (Clementini+, 2023)J/A+A/677/A177 : EPA K2 first-overtone RR Lyrae analysis (Netzel+, 2023)http://www.ztf.caltech.edu/ : The Zwicky Transient Facility (ZTF) homepagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/281/38https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/281/38http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/281/38https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/281/38https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/281/38http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/281/38GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/281/38/table1 (RR Lyrae star catalog of ZTF)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/281/38/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/281/38/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/281/38/table1?GETtext/xml+votable180.050000true274.049772.480970.005555555555555556Cone search capability for table J/ApJS/281/38/table2 (RRd star catalog of ZTF)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/281/38/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/281/38/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/281/38/table2?GETtext/xml+votable180.050000true46.817193.02630.005555555555555556Cone search capability for table J/ApJS/281/38/table3 (Catalog of stars in the Gaia RRd with potentially spurious secondary periods)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/281/38/table3?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/281/38/table3?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/281/38/table3?GETtext/xml+votable180.050000true85.7288174.786110.005555555555555556https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/281/38?format=asciiOpticaldefaultJ/ApJS/281/38/table1RR Lyrae star catalog of ZTFrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRRdFlag "d" indicates an RRd star (link to Table 2), "s" indicates a potentially spurious secondary periods (link to Table 3)meta.ref.urlcharID[1/271742] Internal ID numbermeta.idintSimbadSimbad column added by the CDSmeta.ref.urlcharPer[0.2/1] Derived perioddtime.perioddoubleGaiaGaia DR3 source identifier [source_id]meta.id;meta.mainprimarylogFAP[-319.1/-5]? log, false alarm probabilitystat.probabilityfloatnullableRAJ2000Right Ascension, ZTF (J2000)degpos.eq.ra;meta.mainindexedDEJ2000[-30.5/88] Declination, ZTF (J2000)degpos.eq.dec;meta.mainindexedrmag[11.8/21.6] ZTF r-band AB magnitude, meanmagphot.mag;em.opt.R;stat.meanfloate_rmag[0.007/0.22] standard deviation in rmagmagstat.error;phot.mag;em.opt.RfloatAmp[0.003/1] Amplitudemagsrc.var.amplitudefloatNobs[42/17044] Number of observationsmeta.numberintJ/ApJS/281/38/table2RRd star catalog of ZTFGaiaGaia DR3 source identifier [source_id]meta.id;meta.mainDEJ2000[-28/85] Declination, ZTF (J2000)degpos.eq.dec;meta.mainrmag[13/20.4] ZTF r-band AB magnitude, meanmagphot.mag;em.opt.R;stat.meanfloate_rmag[0.009/0.2] Standard deviation in rmagmagstat.error;phot.mag;em.opt.RfloatNobs[98/10137] Number of observationsmeta.numberintSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintID[7/271734] Internal ID numbermeta.idintPer1[0.29/0.6] Primary pulsation perioddtime.perioddoubleAmp1[0.07/0.4] Primary pulsation light-curve amplitudemagsrc.var.amplitudefloatlogFAP1[-319/-8.7]? Log, false alarm probability, Per1stat.probabilityfloatnullablePer2[0.3/0.6] Second pulsation perioddtime.perioddoubleAmp2[0.012/0.22] Second pulsation light-curve amplitudemagsrc.var.amplitudefloatlogFAP2[-315.1/-5.1]? Log, false alarm probability, Per2stat.probabilityfloatnullableratio[0.72/0.75] Period ratio, P1O/Pf (1)time.period;arith.ratiodoublePer3[0.12/6]? Third pulsation period, see Section 3.3dtime.perioddoublenullableAmp3[0.009/26]? Third pulsation light-curve amplitudemagsrc.var.amplitudefloatnullableRAJ2000Right Ascension, ZTF (J2000)degpos.eq.ra;meta.mainJ/ApJS/281/38/table3Catalog of stars in the Gaia RRd with potentially spurious secondary periodsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintGaiaGaia DR3 source identifier [source_id]meta.id;meta.mainRAJ2000[8.4/358] Right Ascension, ZTF (J2000)degpos.eq.ra;meta.mainDEJ2000[-27.8/74.8] Declination, ZTF (J2000)degpos.eq.dec;meta.mainPztf[0.35/0.62] Primary period, ZTF, this workdtime.perioddoublePf-Gaia[0.4/0.62] Fundamental period, Gaia DR3dtime.perioddoubleP1O-Gaia[0.31/0.46] First-overtone period, Gaia DR3dtime.perioddoublermag[14.22/20.22] ZTF r-band AB magnitude, meanmagphot.mag;em.opt.R;stat.meanfloatPasassn[0.33/0.62]? ASAS-SN periods (1)dtime.perioddoublenullableType? ASAS-SN type (RRAB, RRC or RRD) (1)src.class;src.varcharSimbadSimbad column added by the CDSmeta.ref.urlchar