J/ApJ/886/10ivo://CDS.VizieR/J/ApJ/886/10doi:10.26093/cds/vizier.18860010CDSThomas G.F.Annau N.Mcconnachie A.Fabbro S.Teimoorinia H.Cote P.,Cuillandre J.-C.Gwyn S.Ibata R.A.Starkenburg E.Carlberg R.,Famaey B.Fantin N.Ferrarese L.Henault-brunet V.Jensen J.,Lancon A.Lewis G.F.Martin N.F.Navarro J.F.Reyle C.,Sanchez-janssen R.2021-06-16T12:10:48Z2020-03-05T07:56:28ZCDS support team

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

cds-question@unistra.frmilky-way-galaxygiant-starsdwarf-starsmetallicitystellar-distancephotometryWe present a new fully data-driven algorithm that uses photometric data from the Canada-France Imaging Survey (CFIS; u), Pan-STARRS 1 (PS1; griz), and Gaia (G) to discriminate between dwarf and giant stars and to estimate their distances and metallicities. The algorithm is trained and tested using the Sloan Digital Sky Survey (SDSS)/SEGUE spectroscopic data set and Gaia photometric/astrometric data set. At [Fe/H]<-1.2, the algorithm succeeds in identifying more than 70% of the giants in the training/test set, with a dwarf contamination fraction below 30% (with respect to the SDSS/SEGUE data set). The photometric metallicity estimates have uncertainties better than 0.2dex when compared with the spectroscopic measurements. The distances estimated by the algorithm are valid out to a distance of at least ~80kpc without requiring any prior on the stellar distribution and have fully independent uncertainties that take into account both random and systematic errors. These advances allow us to estimate these stellar parameters for approximately 12 million stars in the photometric data set. This will enable studies involving the chemical mapping of the distant outer disk and the stellar halo, including their kinematics using the Gaia proper motions. This type of algorithm can be applied in the southern hemisphere to the first release of LSST data, thus providing an almost complete view of the external components of our Galaxy out to at least ~80kpc. Critical to the success of these efforts will be ensuring well-defined spectroscopic training sets that sample a broad range of stellar parameters with minimal biases. A catalog containing the training/test set and all relevant parameters within the public footprint of CFIS is available online.2019ApJ...886...10Thttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/886/10CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/886/10https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/886/10http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/886/10https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/886/10https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/886/10http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/886/10GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/886/10/catalog (Training/testing catalog, dwarf or giant)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/886/10/catalog?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/886/10/catalog?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/886/10/catalog?GETtext/xml+votable180.050000true132.367672211.3254620.0055555555555555563/78 97 100 4/287 303 309 311 316 317 318 324 325 327 328 334 335 339 340 341 352 354 355 361 404 408 535 540 541 542 570 576 577 580 646 648 649 650 1759 1779 1780 1782 1784 1786 1790 2027 5/224 226 227 231 242 243 248 523 551 1143 1147 1207 1211 1227 1228 1230 1231 1232 1233 1235 1241 1242 1243 1276 1277 1278 1287 1291 1292 1294 1295 1304 1305 1307 1316 1317 1318 1323 1325 1326 1327 1328 1329 1330 1333 1334 1335 1344 1345 1347 1348 1350 1351 1353 1354 1355 1368 1370 1371 1372 1376 1378 1379 1380 1381 1382 1384 1386 1387 1388 1392 1412 1413 1415 1424 1425 1428 1429 1431 1432 1434 1435 1440 1441 1442 1456 1472 1549 1584 1585 1588 1589 1620 1624 1636 1637 1640 1641 1644 1648 2133 2134 2135 2137 2138 2150 2151 2153 2155 2156 2157 2158 2172 2173 2174 2231 2235 2237 2238 2244 2245 2247 2251 2252 2253 2254 2257 2258 2267 2269 2272 2275 2276 2278 2279 2284 2285 2286 2288 2289 2290 2312 2313 2315 2316 2318 2324 2326 2328 2329 2336 2338 2339 2545 2547 2567 2571 2572 2574 2575 2577 2578 2579 2580 2581 2583 2589 2590 2605 2608 2610 2624 2625 2688 2689 2690 3164 3165 3332 4987 4988 5038 5042 5069 5071 5087 5109 7031 7035 7095 7099 7100 7101 7102 7111 7115 7125 7127 7132 7140 7141 7143 7149 7150 7152 7153 7154 7164 7166 8102 8103 8114 8119 8120 8122 8125 8127 8139 8170 6/725 726 727 732 733 900 902 903 914 920 922 948 949 951 996 997 998 2073 2075 2076 2086 2087 2089 2090 2091 2106 2177 2180 2181 2198 2199 2201 2203 2228 2229 2242 2248 2249 2250 2272 2600 2602 2688 4253 4255 4296 4298 4399 4410 4432 4433 4435 4436 4565 4567 4571 4581 4583 4585 4587 4782 4783 4821 4822 4823 4825 4827 4837 4839 4841 4842 4843 4885 4886 4887 4891 4892 4893 4895 4906 4907 4916 4918 4919 4936 4938 4939 4961 4962 4963 5116 5117 5118 5141 5142 5143 5145 5147 5157 5158 5159 5162 5163 5172 5173 5174 5226 5227 5277 5278 5279 5280 5282 5283 5284 5285 5287 5289 5290 5291 5297 5298 5299 5324 5325 5326 5328 5330 5331 5384 5385 5387 5397 5398 5399 5408 5409 5410 5476 5478 5479 5492 5509 5511 5532 5533 5534 5540 5541 5543 5560 5572 5657 5658 5659 5704 5705 5707 5708 5709 5710 5720 5732 5734 5773 5774 5792 5794 5809 5812 5828 5832 5892 5896 6148 6149 6165 6166 6167 6172 6173 6205 6207 6293 6294 6295 6300 6301 6303 6344 6345 6346 6365 6366 6367 6385 6388 6389 6391 6396 6397 6488 6500 6504 6552 6553 6554 6557 6558 6559 6568 6569 6600 6601 6602 8509 8511 8525 8526 8527 8529 8531 8545 8546 8547 8556 8557 8559 8589 8591 8593 8594 8595 8596 8598 8599 8609 8611 8616 8617 8637 8638 8639 8700 8918 8919 8923 8933 8935 8937 8938 8944 8945 8947 8956 8957 8958 8964 8965 8967 8985 8987 8998 8999 9002 9003 9020 9022 9023 9024 9025 9026 9036 9046 9047 9051 9052 9053 9054 9063 9067 9072 9073 9074 9080 9081 9082 9084 9093 9094 9095 9096 9098 9099 9108 9109 9111 9164 9168 9184 9257 9259 9268 9269 9270 9276 9300 9301 9302 9320 9321 9324 9328 9348 9349 9350 9360 9370 9376 9377 9380 9381 9382 9384 9386 9387 9392 10093 10094 10095 10104 10106 10107 10177 10185 10192 10193 10194 10200 10209 10212 10262 10263 10267 10277 10278 10279 10281 10282 10283 10293 10294 10295 10304 10305 10307 10328 10330 10331 10352 10353 10354 10416 10418 10419 10424 10425 10426 10428 10436 10437 10439 10444 10448 10464 10505 10506 10508 10528 10764 12635 12638 12639 12664 12665 12668 13317 13319 13332 13334 19930 19931 19941 19942 19943 19945 19946 19947 19960 20119 20125 20127 20143 20158 20162 20163 20166 20172 20174 20192 20193 20196 20249 20250 20251 20252 20254 20261 20272 20273 20275 20281 20289 20292 20322 20328 20330 20347 20433 20435 27643 28119 28121 28122 28123 28133 28134 28135 28139 28373 28377 28378 28379 28391 28393 28395 28413 28414 28415 28439 28441 28442 28443 28454 28455 28458 28459 28496 28497 28498 28504 28505 28507 28532 28533 28534 28536 28537 28538 28540 28569 28570 28571 28593 28594 28595 28604 28605 28606 28620 28621 28622 28624 28668 28669 28670 31742 31743 32397 32399 32402 32406 32421 32422 32423 32425 32427 32429 32430 32431 32460 32462 32484 32486 32492 32494 32495 32497 32506 32507 32519 32524 32525 32538 32539 32550 32551 32553 32554 32555 32640 32641 32644 32648 32650 32651 32672 32674 326841.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/886/10?format=asciidefaultJ/ApJ/886/10/catalogTraining/testing catalog, dwarf or giantu0cfisDereddened u-band photometry (u0_cfis)magphot.mag;em.opt.UdoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintRAJ2000Right ascension (J2000) (RA)degpos.eq.ra;meta.mainindexedDEJ2000Declination (J2000) (Dec)degpos.eq.dec;meta.mainindexeducfisu-band photometry (u_cfis)magphot.mag;em.opt.Udoublee_ucfisUncertainty on the u-band photometry (du_cfis)magstat.errordoublegPSPS1 mean g-PSF photometry (g_PS)magphot.mag;em.opt.Bdoubleg0PSDereddened PS1 mean g-PSF photometry (g0_PS)magphot.mag;em.opt.Bdoublee_gPSUncertainty on the g-band photometry (dg_PS)magstat.errordoublerPSPS1 mean r-PSF photometry (r_PS)magphot.mag;em.opt.Rdoubler0PSDereddened PS1 mean r-PSF photometry (r0_PS)magphot.mag;em.opt.Rdoublee_rPSUncertainty on the r-band photometry (dr_PS)magstat.errordoubleiPSPS1 mean i-PSF photometry (i_PS)magphot.mag;em.opt.Idoublei0PSDereddened PS1 mean i-PSF photometry (i0_PS)magphot.mag;em.opt.Idoublee_iPSUncertainty on the i-band photometry (di_PS)magstat.errordoublezPSPS1 mean z-PSF photometry (z_PS)magphot.mag;em.opt.Idoublez0PSDereddened PS1 mean z-PSF photometry (z0_PS)magphot.mag;em.opt.Idoublee_zPSUncertainty on the z-band photometry (dz_PS)magstat.errordoubleyPS? PS1 mean y-PSF photometry (y_PS)magphot.mag;em.IR.Jdoublenullabley0PS? Dereddened PS1 mean y-PSF photometry (y0_PS)magphot.mag;em.IR.Jdoublenullablee_yPS? Uncertainty on the y-band photometry (dy_PS)magstat.errordoublenullableGmagGaia G-band photometry (G_gaia)magphot.mag;em.optdoubleG0magDereddened Gaia G-band photometry (G0_gaia)magphot.mag;em.optdoublee_GmagUncertainty on the Gaia G-band photometry (dG_gaia)magstat.error;phot.mag;em.opt.BdoubleBPmag? Gaia BP-band photometry (BP_gaia)magphot.mag;em.opt.BdoublenullableBP0mag? Dereddened Gaia BP-band photometry (BP0_gaia)magphot.mag;em.opt.Bdoublenullablee_BPmag? Uncertainty on the Gaia BP-band photometry (dBP_gaia)magstat.error;phot.magdoublenullableRPmag? Gaia RP-band photometry (RP_gaia)magphot.mag;em.opt.RdoublenullableRP0mag? Dereddened Gaia RP-band photometry (RP0_gaia)magphot.mag;em.opt.Rdoublenullablee_RPmag? Uncertainty on the Gaia RP-band photometry (dRP_gaia)magstat.error;phot.magdoublenullableplx? Gaia parallax (parallax)maspos.parallax.trigdoublenullablee_plx? Uncertainty on the Gaia parallax (dparallax)masstat.error;pos.parallaxdoublenullablepmRA? Gaia proper motion in R.A. direction, pmRA*DE (pmra)mas/yrpos.pm;pos.eq.radoublenullablee_pmRA? Uncertainty on the Gaia proper motion in R.A. direction (dpmra)mas/yrstat.error;pos.pm;pos.eq.rafloatnullablepmDE? Gaia proper motion in declination direction (pmdec)mas/yrpos.pm;pos.eq.decdoublenullablee_pmDE? Uncertainty on the Gaia proper motion in declination direction (dpmdec)mas/yrstat.error;pos.pm;pos.eq.decfloatnullableE(B-V)Extinction from Schlegel et al. (1998ApJ...500..525S) (EBV)magphot.color.excessdoublePdwarf[0/1] Probability of being a dwarf (proba_dwarf)stat.fit.goodnessdoublePgiant[0/1] Probability of being a giant (=1-proba_dwarf) (proba_giant)stat.fit.goodnessdoublee_Pgiant? Uncertainty on the probability to be a dwarf/giant (dproba_giant)stat.errordoublenullable[Fe/H]pPredicted photometric metallicity (equal to feh_dwarf if proba_dwarf>0.5 and to feh_giant if proba_giant>0.5) (feh_pred)phys.abund.Zfloate_[Fe/H]pSystematic error on the predicted photometric metallicity (dfeh_pred_sys)stat.error;phys.abund.Fefloate_[Fe/H]pphPhotometric uncertainty on the predicted photometric metallicity (dfeh_pred_photo)stat.error;phys.abund.FefloatGMAGpPredicted absolute magnitude (equal to MG_dwarf if proba_dwarf>0.5 and to MG_giant if proba_giant>0.5) (MG_pred)magphys.magAbs;em.opt.Bdoublee_GMAGpSystematic error on the predicted absolute magnitude (dMG_pred_sys)magstat.errordoublee_GMAGpphUncertainty on the predicted absolute magnitude (dMG_pred_photo)magstat.errordouble[Fe/H]pdwPredicted photometric metallicity using the dwarf calibration (feh_dwarf)phys.abund.Fefloate_[Fe/H]pdwSystematic error on the predicted photometric metallicity of the dwarfs (dfeh_dwarf_sys)stat.error;phys.abund.Fefloate_[Fe/H]pdwphPhotometric uncertainty on the predicted photometric metallicity of the dwarfs (dfeh_dwarf_photo)stat.error;phys.abund.FefloatGMAGpdwPredicted absolute magnitude using the dwarf calibration (MG_dwarf)magphys.magAbs;em.opt.B;src.calibdoublee_GMAGpdwSystematic error on the predicted absolute magnitude of the dwarfs (dMG_dwarf_sys)magstat.errordoublee_GMAMApdwphUncertainty on the predicted absolute magnitude of dwarfs (dMG_dwarf_photo)magstat.errordouble[Fe/H]pgPredicted photometric metallicity using the giant calibration (feh_giant)phys.abund.Fefloate_[Fe/H]pgSystematic error on the predicted photometric metallicity of the giants (dfeh_giant_sys)stat.error;phys.abund.Fefloate_[Fe/H]pgphPhotometric uncertainty on the predicted photometric metallicity of the giants (dfeh_giant_photo)stat.error;phys.abund.FefloatGMAGpgPredicted absolute magnitude using the giant calibration (MG_giant)magphys.magAbs;em.opt.B;obs.calibdoublee_GMAGpgSystematic error on the predicted absolute magnitude of the giants (dMG_giant_sys)magstat.errordoublee_GMAGpgphUncertainty on the predicted absolute magnitude of giants (dMG_giant_photo)magstat.errordoubleDistpHeliocentric distance using the predicted absolute magnitude (kpc) (dist_pred)kpcpos.distancefloatGMAG? Absolute magnitude computed from the Gaia parallaxes (MG_gaia)magphys.magAbs;meta.modelleddoublenullablee_GMAG? Uncertainty on the absolute magnitude from Gaia parallaxes (dMG_gaia)magstat.errordoublenullableobjIDObject ID from SDSS/SEGUE (objid)meta.idspecobjIDSpectrocopic ID from SDSS/SEGUE (specobjID)meta.idTeffAdopted effective temperature from SDSS/SEGUE (in Kelvin) (Teffadop)Kphys.temperature.effectivedoublee_TeffUncertainty on the adopted effective temperature from SDSS/SEGUE (Teffadopunc)Kstat.error;phys.temperature.effectivedoubleloggAdopted surface gravity from SDSS/SEGUE (loggadop)log(cm.s**-2)phys.gravitydoublee_loggUncertainty on the adopted surface gravity from SDSS/SEGUE (loggadopunc)log(cm.s**-2)stat.errordouble[Fe/H]Adopted spectroscopic metallicity from SDSS/SEGUE (FeHadop)phys.abund.Zfloate_[Fe/H]Uncertainty on the adopted spectroscopic metallicity from SDSS/SEGUE (FeHadopunc)stat.error;phys.abund.FefloatSNRSpectroscopic S/N from SDSS/SEGUE (snr)stat.snrdouble