J/AJ/158/16ivo://CDS.VizieR/J/AJ/158/16doi:10.26093/cds/vizier.51580016CDSStringer K.M.Long J.P.Macri L.M.Marshall J.L.Drlica-Wagner A.,Martinez-Vazquez C.E.Vivas A.K.Bechtol K.Morganson E.,Carrasco Kind M.Pace A.B.Walker A.R.Nielsen C.Li T.S.Rykoff E.,Burke D.Carnero Rosell A.Neilsen E.Ferguson P.Cantu S.A.,Myron J.L.Strigari L.Farahi A.Paz-Chinchon F.Tucker D.Lin Z.,Hatt D.Maner J.F.Plybon L.Riley A.H.Nadler E.O.Abbott T.M.C.,Allam S.Annis J.Bertin E.Brooks D.Buckley-Geer E.Carretero J.,Cunha C.E.D'Andrea C.B.da Costa L.N.De Vicente J.Desai S.Doel P.,Eifler T.F.Flaugher B.Frieman J.Garcia-Bellido J.Gaztanaga E.,Gruen D.Gschwend J.Gutierrez G.Hartley W.G.Hollowood D.L.,Hoyle B.James D.J.Kuehn K.Kuropatkin N.Melchior P.Miquel R.,Ogando R.L.C.Plazas A.A.Sanchez E.Santiago B.Scarpine V.,Schubnell M.Serrano S.Sevilla-Noarbe I.Smith M.Smith R.C.,Soares-Santos M.Sobreira F.Suchyta E.Swanson M.E.C.Tarle G.,Thomas D.Vikram V.Yanny B.2021-02-18T11:30:53Z2019-09-13T09:37:33ZCDS support team

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

cds-question@unistra.frvariable-starsinfrared-photometryvisible-astronomybroad-band-photometryastronomical-object-identificationMany studies have shown that RR Lyrae variable stars (RRL) are powerful stellar tracers of Galactic halo structure and satellite galaxies. The Dark Energy Survey (DES), with its deep and wide coverage (g~23.5 mag in a single exposure; over 5000 deg^2^) provides a rich opportunity to search for substructures out to the edge of the Milky Way halo. However, the sparse and unevenly sampled multiband light curves from the DES wide-field survey (a median of four observations in each of grizY over the first three years) pose a challenge for traditional techniques used to detect RRL. We present an empirically motivated and computationally efficient template-fitting method to identify these variable stars using three years of DES data. When tested on DES light curves of previously classified objects in SDSS stripe 82, our algorithm recovers 89% of RRL periods to within 1% of their true value with 85% purity and 76% completeness. Using this method, we identify 5783 RRL candidates, ~28% of which are previously undiscovered. This method will be useful for identifying RRL in other sparse multiband data sets.2019AJ....158...16Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/158/16CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/gcvs : General Catalogue of Variable Stars (Samus+, 2007-2017)II/294 : The SDSS Photometric Catalog, Release 7 (Adelman-McCarthy+, 2009)I/345 : Gaia DR2 (Gaia Collaboration, 2018)II/357 : The Dark Energy Survey (DES): Data Release 1 (Abbott+, 2018)J/PAZh/27/132 : Parameters of RR Lyrae Type Variables (Dambis+, 2001)J/AJ/134/973 : SDSS Stripe 82 star catalogs (Ivezic+, 2007)J/MNRAS/398/1757 : RR Lyraes in SDSS stripe 82 (Watkins+, 2009)J/ApJ/708/717 : Light curve templates of RR Lyrae stars (Sesar+, 2010)J/MNRAS/424/2528 : RR Lyrae in SDSS Stripe 82 (Suveges+, 2012)J/ApJ/763/32 : Galactic halo RRab stars from CSS (Drake+, 2013)J/ApJ/765/154 : RR Lyrae stars in the Catalina Sky Survey (Drake+, 2013)J/MNRAS/441/1230 : RRLyr stars in the Catalina Sky Survey (CS2) (Abbas+, 2014)J/MNRAS/446/2251 : Southern Catalina Survey type-ab RR Lyrae (Torrealba+, 2015)J/MNRAS/462/4349 : Variable stars in Sculptor dSph (Martinez-Vazquez+, 2016)J/AcA/67/297 : OGLE Galactic center Cepheids & RR Lyrae (Soszynski+, 2017)J/AJ/153/204 : RR Lyrae stars from the PS1 3{pi} survey (Sesar+, 2017)J/ApJ/834/160 : ugriz colors of RR Lyrae in SDSS Stripe 82 (Ngeow+, 2017)J/ApJ/849/150 : RR Lyrae candidates in the MW outer halo (Cohen+, 2017)J/MNRAS/469/3688 : CSS Periodic Variable Star Catalogue (Drake+, 2017)J/AJ/156/241 : A first cat. of variables measured by ATLAS (Heinze+, 2018)J/ApJ/863/79 : RR Lyrae cand. in Galactic Center (Contreras Ramos+, 2018)J/A+A/622/A60 : Gaia DR2 misclassified RR Lyrae list (Clementini+, 2019)http://des.ncsa.illinois.edu/releases/other/y3-rrl : Online Yr 3 RR Lyrae cat.https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/158/16https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/158/16http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/158/16https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/158/16https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/158/16http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/158/16GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/158/16/table6 (DES RRab candidates)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/158/16/table6?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/158/16/table6?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/158/16/table6?GETtext/xml+votable180.050000true0.00010694-59.559186940.005555555555555556Cone search capability for table J/AJ/158/16/table11 (Full catalog of RRab candidates)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/158/16/table11?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/158/16/table11?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/158/16/table11?GETtext/xml+votable180.050000true50.1223496001495-52.03598140523690.0055555555555555561/33 34 2/131 140 142 179 180 3/260 261 273 276 277 278 281 282 322 328 519 564 565 566 572 574 711 724 728 4/1024 1025 1028 1029 1031 1085 1088 1089 1090 1101 1102 1103 1116 1121 1122 1123 1132 1136 1173 1174 1177 1178 1189 1190 1193 1216 1280 1282 1283 1294 1316 1318 1320 1321 1322 2071 2075 2087 2091 2093 2094 2095 2268 2270 2292 2302 2434 2440 2442 2464 2466 2472 2474 2839 2843 2900 2901 2904 2905 2906 2916 2918 2920 2921 2964 2965 5/0 2 8 9 10 4108 4109 4120 4121 4123 4319 4337 4339 4348 4349 4351 4364 4365 4366 4397 4399 4401 4403 4468 4469 4470 4472 4473 4474 4483 4532 4533 4534 4536 4537 4538 4548 4549 4550 4552 4553 4554 4671 4685 4686 4687 4689 4691 4700 4705 4706 4707 4716 4717 4718 4720 4722 4749 4750 4751 4753 4754 4755 4764 4765 4769 4770 4771 4776 4777 4779 4780 4781 4782 4784 4786 4800 4801 4802 4868 4869 5124 5126 5127 5146 5168 5170 5171 5180 5182 5268 5270 5276 5292 5296 5632 6814 8279 8283 8293 8294 8295 8299 8347 8359 8369 8370 8371 9076 9077 9078 9084 9086 9172 9176 9177 9178 9202 9203 9212 9214 9215 9730 9742 9743 9766 9902 11355 11367 11415 11421 11423 11445 11447 11453 11455 11608 11609 11610 11612 11628 11632 11668 11669 11670 11676 11688 11689 11690 11712 11840 11841 11843 11844 11845 11847 11864 11865 11868 12032 6/6 12 14 15 44 48 128 12292 12293 16416 16417 16420 16421 16596 16597 16772 16773 16784 16785 16788 16789 16832 16833 16836 16837 16848 16849 16850 16852 16853 17247 17269 17270 17271 17273 17274 17275 17381 17383 17391 17401 17402 17403 17468 17469 17471 17536 17537 17538 17540 17541 17557 17583 17593 17594 17595 17600 17601 17609 17610 17611 17884 17885 17900 17901 17904 17905 17925 17926 17927 17929 17930 17931 18140 18142 18156 18160 18161 18204 18206 18220 18222 18224 18226 18240 18241 18242 18304 18655 18671 18675 18677 18678 18679 18681 18682 18683 18755 18761 18762 18763 18804 18805 18806 18808 18809 18810 18812 18884 18885 18886 18892 18896 19064 19065 19066 19112 19113 19115 19140 19141 19142 19168 19212 19480 19481 19482 19484 19486 19488 19520 19521 19522 20502 20576 20578 20579 20676 20678 20679 20698 21076 21078 21084 21086 21112 21113 21172 21176 21177 21188 21192 21194 22532 22536 22537 22538 22560 22562 22568 22570 22656 22658 23210 27245 27247 27250 27251 27260 27344 27345 33087 33109 33111 33115 33126 33127 33129 33130 33131 33169 33170 33171 33195 33367 33371 33373 33374 33375 33387 33431 33447 33451 33453 33454 33455 33473 33474 33475 36316 36317 36318 36340 36342 36348 36350 36696 36698 36716 36718 36800 36802 36803 38912 38914 38915 38926 38927 38960 38962 38965 38966 38967 39008 39010 39016 39056 39058 39059 39088 39089 39090 39096 39098 39440 39442 39448 39450 39472 39474 39480 39482 39568 39570 39600 39602 45399 45403 45405 45406 45407 45419 45463 45479 45483 45485 45486 45487 45659 45681 45682 45683 45688 45689 45691 45809 45811 46444 46445 46446 46452 46453 46456 46516 46520 46532 46684 46685 46686 46708 46764 46765 46766 46768 46769 46770 46772 46784 46785 46786 46788 46789 46792 46856 47188 47189 47191 47368 47369 47371 47385 47387 47412 47413 47415 47464 47465 47467 47468 47469 47470 47476 47478 47480 48136 49119 49141 491432.3230668610021367e-19 4.973527819473193e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/158/16?format=asciiOpticalInfrareddefaultJ/AJ/158/16/table6DES RRab candidatesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDDES internal Year 3 Quick Release catalog (Y3Q2) object IDmeta.id;meta.mainRAJ2000Right Ascension in decimal degrees (J2000)degpos.eq.ra;meta.mainDEJ2000Declination in decimal degrees (J2000)degpos.eq.dec;meta.maingmagmean[15.213/22.757]? Mean g band (AB) magnitudemagphot.mag;em.opt.Bfloatnullablermagmean[15.361/22.733]? Mean r band (AB) magnitudemagphot.mag;em.opt.Rfloatnullableimagmean[15.373/22.604]? Mean i band (AB) magnitudemagphot.mag;em.opt.Ifloatnullablezmagmean[15.356/22.77]? Mean z band (AB) magnitudemagphot.mag;em.opt.IfloatnullableYmagmean[15.367/21.587]? Mean Y band (AB) magnitudemagphot.mag;em.IR.JfloatnullablePer[0.437/0.8227] Perioddtime.periodfloatAmp[0.233/1.556] Best-fit model amplitudemagsrc.var.amplitude;meta.modelledfloatmu[14.71/21.82] Distance modulus {mu}magphot.mag.distModfloatp[0.35/0.949] RRab score assigned by the classifiermeta.code.classfloatJ/AJ/158/16/table11Full catalog of RRab candidatesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDDES Y3Q2 ID numbermeta.id;meta.mainprimaryID1DES DR1 ID number (0=not found in DES DR1 coadd catalog, Abbott et al. 2018ApJS..239...18A)meta.idlongRAJ2000Right Ascension in decimal degress (J2000)degpos.eq.ra;meta.mainindexedDEJ2000Declination in decimal degress (J2000)degpos.eq.dec;meta.mainindexedp-ab[9.24104e-05/0.949354] Classifier score for RRab classmeta.code.classdoubleEBV[0.000463673/0.585073] Extinction value from Schlegel et al. (1998ApJ...500..525S) (1)phot.color.excessdoublegmagmean[-22.3208/24.531]? Mean g (AB) magnitude measured in light curves (2)magphot.mag;em.opt.Bdoublenullablermagmean[-11.1642/24.7026]? Mean r (AB) magnitude measured in light curves (2)magphot.mag;em.opt.Rdoublenullableimagmean[-11.2687/24.5309]? Mean i (AB) magnitude measured in light curves (2)magphot.mag;em.opt.Idoublenullablezmagmean[-11.3202/24.5309]? Mean z (AB) magnitude measured in light curves (2)magphot.mag;em.opt.IdoublenullableYmagmean[-12.1138/24.5309]? Mean Y (AB) magnitude measured in light curves (2)magphot.mag;em.IR.JdoublenullableNobs-g[0/33] Number of observations in DES gmeta.numberintNobs-r[0/37] Number of observations in DES rmeta.numberintNobs-i[0/61] Number of observations in DES imeta.numberintNobs-z[0/62] Number of observations in DES zmeta.numberintNobs-Y[0/41] Number of observations in DES Ymeta.numberintNobs[5/194] Total number of observations across all bandsmeta.numberintPer0[0.434792/0.892838] Period of best fitting templatedtime.perioddoublePer1[0.434792/0.892838] Period of 2nd best fitting templatedtime.perioddoublePer2[0.434792/0.892838] Period of 3rd best fitting templatedtime.perioddoublesigma-DP/P[0.006/0.293]? Uncertainty in (P_est_-P_true_)/P of the best fit periodstat.errordoublenullableAmp0[0.000303309/1589.18] Amplitude of best fitting template (3)magsrc.var.amplitudedoubleAmp1[7.22078e-05/817.171] Amplitude of 2nd best fitting templatemagsrc.var.amplitudedoubleAmp2[3.93605e-05/760.817] Amplitude of 3rd best fitting templatemagsrc.var.amplitudedoublesigma-Da[-0.012/0.903]? Uncertainty in (a_est_-a_true_) of the best fit amplitudemagstat.errordoublenullablemu0[-219.091/108.275] Distance modulus of best fitting templatemagphot.mag.distModdoublemu1[-114.919/56.2675] Distance modulus of 2nd best fitting templatemagphot.mag.distModdoublemu2[-194.008/54.6556] Distance modulus of 3rd best fitting templatemagphot.mag.distModdoublePhase0[9.62361e-07/1] Phase offset of best fitting templatetime.phasedoublePhase1[3.06546e-06/1] Phase offset of 2nd best fitting templatepos.angDistance;meta.modelleddoublePhase2[3.93540e-06/0.999996] Phase offset of 3rd best fitting templatepos.angDistance;meta.modelleddoubleRSS0[3.99068e-07/696961]? Residual Sum of Squares (RSS) of best fit templatestat.fit.residualdoublenullableRSS1[5.9748e-05/701646]? RSS of 2nd best fit templatestat.fit.residualdoublenullableRSS2[9.8591e-05/702625]? RSS of 3rd best fit templatestat.fit.residualdoublenullablechi2-g[1.82028e-06/3.2428e+46]? Reduced chi squared of light curve from constant in DES g (4)stat.fit.chi2doublenullablef_chi2-g[I] I for infinitymeta.codecharchi2-r[2.14514e-06/1.45597e+51]? Reduced chi squared of light curve from constant in DES r (4)stat.fit.chi2doublenullablechi2-i[5.13706e-07/373528]? Reduced chi squared of light curve from constant in DES i (4)stat.fit.chi2doublenullablef_chi2-i[I] I for infinitymeta.codecharchi2-z[1.52942e-06/545252]? Reduced chi squared of light curve from constant in DES z (4)stat.fit.chi2doublenullablef_chi2-z[I] I for infinitymeta.codecharchi2-Y[1.62728e-07/4.21637e+06]? Reduced chi squared of light curve from constant in DES Y (4)stat.fit.chi2doublenullableSig-g[0/20410.8]? Significance of light curve in DES g (4)stat.fit.goodnessdoublenullableSig-r[0/18028.5]? Significance of light curve in DES r (4)stat.fit.goodnessdoublenullableSig-i[0/30133.6]? Significance of light curve in DES i (4)stat.fit.goodnessdoublenullableSig-z[0/23563.7]? Significance of light curve in DES z (4)stat.fit.goodnessdoublenullableSig-Y[0/14540.5]? Significance of light curve in DES Y (4)stat.fit.goodnessdoublenullableRSS-dof-0[3.99068e-07/9949.94]? RSS per degree of freedom of best fitting template (3)stat.fit.residualdoublenullableRSS-dof-1[5.9748e-05/109327]? RSS per degree of freedom of 2nd best fitting templatestat.fit.residualdoublenullableRSS-dof-2[9.8591e-05/109651]? RSS per degree of freedom of 3rd best fitting templatestat.fit.residualdoublenullableIchi-med[-2.93188/51.3637]? Median log(reduced chi squared) across DES grizY (3)stat.fit.chi2doublenullableRSS-Ichi-med[-999.467/9991.97]? (RSS/dof)/median log(reduced chi squared) across DES grizY (3)stat.fit.paramdoublenullableAmp-RSS-0[0.00011072/9970.12]? Best-fitting amplitude divided by the best-fitting RSS/dof (3)stat.fit.paramdoublenullablef-dist1-0[0.000139949/1587.71] Distance of Amplitude/Period for best fit template (3) (5)pos.distancedoublef-dist1-1[0.000131378/815.706]? Distance of Amplitude/Period for 2nd best fit template (5)pos.distancedoublenullablef-dist1-2[0.00011433/759.352]? Distance of Amplitude/Period for 3rd best fit template (5)pos.distancedoublenullablef-dist2-0[0.000181306/1587.71]? Distance of Amplitude/Period for best fit template (3) (6)pos.distancedoublenullablef-dist2-1[0.000175503/815.706]? Distance of Amplitude/Period for 2nd best fit template (6)pos.distancedoublenullablef-dist2-2[0.000101131/759.352]? Distance of Amplitude/Period for 3rd best fit template (6)pos.distancedoublenullablekappa-0[0.000564259/9972.2]? von Mises-Fisher concentration parameter of phases for best fitting template (3)stat.paramdoublenullablekappa-1[0.000306927/18264.3]? von Mises-Fisher concentration parameter of phases for 2nd best fitting templatestat.paramdoublenullablekappa-2[0.000383926/18628.4]? von Mises-Fisher concentration parameter of phases for 3rd best fitting templatestat.paramdoublenullableflag-minmax[0/3]? Flag for observations missing near maximum and minimum light (7)meta.code.errorintnullableSourceGaia DR2 source_id for cross-matched RRab in Clementini et al. (2018, J/A+A/622/A60) (0=not found in this catalog)meta.idPS1-RRab[0/1] Present in Sesar et al. (2017, J/AJ/153/204) RRab catalog? (0=No; 1=Yes)meta.codeintCSDR2-IDID number from associated Catalina Surveys DR2 RRab catalogs (0=not found in this catalog)meta.idATLAS-IDID from Heinze et al. (2018, J/AJ/156/241) ATLAS RRab catalog (0=not found in this catalog)meta.idcharSDSS-ID[0/7913279] SDSS DR7 (Cat. II/294) ID (0=not found in this catalog)meta.idintSDSS-classClassification from SDSS stripe 82 studies from Sesar et al. (2010, J/ApJ/708/717) or Ivezic et al. (2007, J/AJ/134/973) (8)meta.code.classcharSimbad-IDObject identifier in SIMBAD database (0=not found in this catalog)meta.idcharSimbad-classObject classification in SIMBAD database (0=not found in this catalog)meta.code.classcharOGLE-IDOGLE ID from LMC and SMC RRAb catalogs from Soszynski et al. (2016AcA....66..131S)meta.idcharCEMV-IDID from Martinez-Vazquez et al. (2016, J/MNRAS/462/4349) (0=not found in this catalog)meta.idcharGCVS5-ID[0/820079] Cross matched ID with the General Catalogue of Variable Stars v5.1 from Samus et al. (2017, Cat. B/gcvs) (0=not found in this catalog)meta.idintGCVS5-TypeVariable type for cross matched object (see file "vartype.txt" in the General Catalogue of Variable Stars v5.1)meta.code.classcharhpx32[5441/11819] Object's Healpix (nside=32) used to subdivide the light curvesobs.fieldinttrain[0/1] Identifies objects used to train the Random Forest (0=not in training set; 1=in training set)meta.codeintrrab[0/1] Identified as a high confidence RRab in this study (=1) or not (=0)meta.codeintFileFilepath to the object's light curves in subdirectory lcphys.composition.massLightRatiocharComComment from first author during visual validation (9)meta.notecharJ/AJ/158/16/table1*Error rescaling coefficients for Equation (2)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintHEALPix[5441/11877] HEALPix regionpos.healpix;obs.fieldintBand[grizY] DES filter namemeta.code;instr.filtercharc0[-0.7953/2.0858]? Error correct coefficient 0 for Bandstat.errorfloatnullablec1[-0.6321/0.3225]? Error correct coefficient 1 for Bandstat.errorfloatnullablec2[-0.2069/0.0509]? Error correct coefficient 2 for Bandstat.errorfloatnullableJ/AJ/158/16/table5Estimated RRab selection purity & completenessrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintThrsh[0/0.99] Score thresholdstatfloatPur[0/1] Purity (1)statfloatComp[0/0.983] Completeness (2)meta.notefloat