J/ApJS/261/31ivo://CDS.VizieR/J/ApJS/261/31doi:10.26093/cds/vizier.22610031CDSBerg D.A.James B.L.King T.McDonald M.Chen Z.Chisholm J.,Heckman T.Martin C.L.Stark D.P.Aloisi A.Amorin R.O.,Arellano-Cordova K.Z.Bayliss M.Bordoloi R.Brinchmann J.Charlot S.,Chevallard J.Clark I.Erb D.K.Feltre A.Gronke M.Hayes M.Henry A.,Hernandez S.Jaskot A.Jones T.Kewley L.J.Kumari N.Leitherer C.,Llerena M.Maseda M.Mingozzi M.Nanayakkara T.Ouchi M.Plat A.,Pogge R.W.Ravindranath S.Rigby J.R.Sanders R.Scarlata C.,Senchyna P.Skillman E.D.Steidel C.C.Strom A.L.Sugahara Y.,Wilkins S.M.Wofford A.Xu X.The CLASSY Team2022-11-09T06:25:47Z2022-10-26T12:33:57ZCDS support team

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

cds-question@unistra.frspectroscopyultraviolet-astronomyvisible-astronomygalaxiesredshiftedchemical-abundancesinterstellar-reddeningFar-ultraviolet (FUV; ~1200-2000{AA}) spectra are fundamental to our understanding of star-forming galaxies, providing a unique window on massive stellar populations, chemical evolution, feedback processes, and reionization. The launch of the James Webb Space Telescope will soon usher in a new era, pushing the UV spectroscopic frontier to higher redshifts than ever before; however, its success hinges on a comprehensive understanding of the massive star populations and gas conditions that power the observed UV spectral features. This requires a level of detail that is only possible with a combination of ample wavelength coverage, signal-to-noise, spectral-resolution, and sample diversity that has not yet been achieved by any FUV spectral database. We present the Cosmic Origins Spectrograph Legacy Spectroscopic Survey (CLASSY) treasury and its first high-level science product, the CLASSY atlas. CLASSY builds on the Hubble Space Telescope (HST) archive to construct the first high-quality (S/N_1500{AA}_>~5/resel), high-resolution (R~15000) FUV spectral database of 45 nearby (0.002<z<0.182) star-forming galaxies. The CLASSY atlas, available to the public via the CLASSY website, is the result of optimally extracting and coadding 170 archival+new spectra from 312 orbits of HST observations. The CLASSY sample covers a broad range of properties including stellar mass (6.2<logM_*_(M_{sun}_)<10.1), star formation rate (-2.0<logSFR(M_{sun}_/yr)<+1.6), direct gas-phase metallicity (7.0<12+log(O/H)<8.8), ionization (0.5<O_32_<38.0), reddening (0.02<E(B-V)<0.67), and nebular density (10<n_e_(cm-3)<1120). CLASSY is biased to UV-bright star-forming galaxies, resulting in a sample that is consistent with the z~0 mass-metallicity relationship, but is offset to higher star formation rates by roughly 2dex, similar to z>~2 galaxies. This unique set of properties makes the CLASSY atlas the benchmark training set for star-forming galaxies across cosmic time.2022ApJS..261...31Bhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJS/261/31CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/hst : HST Archived Exposures Catalog (STScI, 2007)II/311 : WISE All-Sky Data Release (Cutri+ 2012)V/147 : The SDSS Photometric Catalogue, Release 12 (Alam+, 2015)II/349 : The Pan-STARRS release 1 (PS1) Survey - DR1 (Chambers+, 2016)II/335 : Revised catalog of GALEX UV sources (GUVcat_AIS GR6+7) (Bianchi+ 2017)V/154 : Sloan Digital Sky Surveys (SDSS), Release 16 (DR16) (Ahumada+, 2020)II/371 : The Dark Energy Survey (DES): Data Release 2 (Abott+, 2021)J/ApJS/178/247 : H{alpha} and [NII] survey in local 11 Mpc (Kennicutt+, 2008)J/ApJ/706/599 : H{alpha} and UV SFR in the local volume (Lee+, 2009)J/ApJS/190/233 : Spectroscopy & abundances of SINGS galaxies (Moustakas+, 2010)J/A+A/561/A64 : Mrk 996 optical spectroscopy (Telles+, 2014)J/ApJ/806/16 : CHemical Abundances of Spirals. I. NGC628 (Berg+, 2015)J/ApJS/219/8 : SFR for WISE + SDSS spectroscopic galaxies (Chang+, 2015)J/ApJ/814/L6 : CIII] emission in near & far star-forming gal. (Rigby+, 2015)J/A+A/608/A139 : 237 Lyman-alpha spectra of MUSE-Wide survey (Gronke, 2017)J/A+A/615/A78 : Spectral models for binary products (Goetberg+, 2018)J/AJ/155/104 : MEGaSaURA. I. The sample and the spectra (Rigby+, 2018)J/ApJ/869/123 : Keck Lyman continuum sp. survey (KLCS) (Steidel+, 2018)J/ApJ/893/96 : CHAOS IV: NGC3184 LBT obs. & 3 other gal. abund. (Berg+, 2020)J/A+A/654/A80 : MUSE Catalog of UV emission line measurement (Schmidt+, 2021)http://archive.stsci.edu/hlsp/classy : CLASSY home pagehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJS/261/31https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJS/261/31http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJS/261/31https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJS/261/31https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJS/261/31http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJS/261/31GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJS/261/31/classy (Ancillary optical spectra (Table 4), spectroscopy-derived properties (Table 5) and photometry-derived properties (Table 6) for the CLASSY galaxy and nominal and measured spectral resolution of CLASSY coadded spectra (Table 3))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJS/261/31/classy?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJS/261/31/classy?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJS/261/31/classy?GETtext/xml+votable180.050000true5.25429170.88002220.005555555555555556Associated datahttps://cdsarc.cds.unistra.fr/assocdata/?obs_collection=J/ApJS/261/316/4948 5026 5351 5359 5458 5556 5647 5669 5814 5964 5995 6010 6459 7259 7281 8268-8269 8328 8716 8778 8897 10472 10587 11239 11782 17614 18098 18198 23078 25851 25938 26142 27199 27409 27431 27855 27884 28180 28269 28460 28617 31487 31623 34430 355761.3242995164608996e-18 1.3242995164608996e-18https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJS/261/31?format=asciiUVOpticaldefaultJ/ApJS/261/31/classyAncillary optical spectra (Table 4), spectroscopy-derived properties (Table 5) and photometry-derived properties (Table 6) for the CLASSY galaxy and nominal and measured spectral resolution of CLASSY coadded spectra (Table 3)fitsDownload the FITS filemeta.ref.urlcharFileNameName of the FITS file in subdirectory "fits"; column added by CDSmeta.id;meta.fitscharSpInteractive spectrum plotmeta.ref.urlcharSeq[1/45] Internal target index numbermeta.id;meta.mainintSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNobsNumber of observations (link to Table 2)meta.numberintnullableNameGalaxy identifier (JHHMM+DDMM)meta.idcharprimaryInstTelescope/spectrograph of optical spectrummeta.id;instrcharApAperture size (1)arcsecphys.angSize;instr.fovcharExpTimeCumulative exposure timestime.duration;obs.exposurecharReferenceReference for the observationsmeta.ref;pos.framecharANameAlternate name(s)meta.idcharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainz[0.0016/0.182] Spectroscopic redshiftsrc.redshiftdoubleF1500[0.69/16.6] Continuum flux at 1500{AA} from the CLASSY coadded spectra; in units of 10^-15^erg/s/cm^2^/{AA}1e-17W.m**-2.nm**-1phot.flux.density;spect.continuumfloatZ[6.98/8.8] Direct method oxygen abundance (12+log (O/H))phys.abundfloate_Z[0.01/11.4] Uncertainty in Zstat.error;src.redshiftfloatr_ZIon temperature used to determine Zmeta.ref;pos.framecharne[10/910] Gas-phase electron densitycm**-3phys.density;phys.electroninte_ne[10/160] Uncertainty in necm**-3stat.errorintO32[0.5/38] The [OIII]5007{AA}/[OII]3727{AA} flux ratiophot.flux;arith.ratiofloate_O32[0.1/3] Uncertainty in O32stat.errorfloatE(B-V)[0.039/0.5] Reddening value from Balmer decrementmagphot.color.excessfloate_E(B-V)[0.004/0.07] Uncertainty in E (B-V)magstat.errorfloatDist[8/880] Luminosity distance (2)Mpcpos.distanceintr50[0.7/7.3] Optical half light radius (3)arcsecphys.angSize;srcfloatMAper[4.9/10] COS aperture log stellar mass (4)log(solMass)phys.massfloatE_MAper[0.12/0.6] Upper uncertainty in MAperlog(solMass)stat.error;stat.maxfloate_MAper[0.09/0.5] Lower uncertainty in MAperlog(solMass)stat.errorfloatMTot[6.2/10.1] Total log stellar mass for entire galaxy (4)log(solMass)phys.massfloatE_MTot[0.15/0.51] Upper uncertainty in MTotlog(solMass)stat.error;stat.maxfloate_MTot[0.1/0.42] Lower uncertainty in MTotlog(solMass)stat.errorfloatSFRAper[-3.1/1.5] Within COS aperture log star formation rate (4)log(solMass.yr**-1)phys.SFR;instr.fovfloatE_SFRAper[0.07/0.3] Upper uncertainty in SFRAperlog(solMass.yr**-1)stat.error;stat.maxfloate_SFRAper[0.08/0.5] Lower uncertainty in SFRAperlog(solMass.yr**-1)stat.errorfloatSFRTot[-2.1/1.6] Total log star formation rate for entire galaxy (4)log(solMass.yr**-1)phys.SFRfloatE_SFRTot[0.07/0.7] Upper uncertainty in SFRTotlog(solMass.yr**-1)stat.error;stat.maxfloate_SFRTot[0.07/0.65] Lower uncertainty in SFRTotlog(solMass.yr**-1)stat.errorfloatlambdaRest-frame wavelength; Angstroms1e-10mem.wlcharVHR[11.6/14.3] Nominal resolution of the VHR spectrum in units of km/s per resolution element (5)km/spos.angResolution;arith.ratiofloatHR[14.2/17.4] Nominal resolution of the HR spectrum in units of km/s per resolution element (5)km/spos.angResolution;arith.ratiofloatMR[38.8/47.6] Nominal resolution of the MR spectrum in units of km/s per resolution element (5)km/spos.angResolution;arith.ratiofloatLR[96.5/119.6] Nominal resolution of the LR spectrum in units of km/s per resolution element (5)km/spos.angResolution;arith.ratiofloatRes[20/128] Resolution of measured absorption feature (6)km/sspect.resolutionintJ/ApJS/261/31/table2CLASSY New+Archival HST/COS observationsSpExpT[356/13852]? Spectrum exposure timestime.duration;obs.exposureintnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/45] Internal target index numbermeta.idintNameGalaxy identifier (JHHMM+DDMM)meta.idcharz[0.0016/0.182] Spectroscopic redshiftsrc.redshiftdoublePID[11523/15840]? HST Program ID (1)meta.id;obsintnullableImDataAcquisition image dataset namemeta.id;meta.dataset;obs.imagecharImExpT[0.6/510]? Acquisition image exposure timestime.duration;obs.image;obs.exposurefloatnullablef_ImExpTNA = Not applicablemeta.codecharImMir[AB] Acquisition image mirrormeta.id;instrcharPA[1/355]? Position angle of aperturedegpos.posAng;instr.fovintnullableImGFWHM[0.1/1.42]? GFWHM along spatial axis of acquisition imagearcsecphys.angSizefloatnullablef_ImGFWHMNA = Not applicablemeta.codecharSpDataSpectrum dataset namemeta.id;meta.datasetcharGratingSpectrum gratingmeta.id;instrcharclambda[1105/2339]? Spectrum central wavelength; in Angstrom units1e-10mem.wl.centralintnullableLP[1/4]? Spectrum lifetime positionmeta.idintnullablef_LPNA = Not applicablemeta.codecharlambdaSt[966.6/1889.3]? Starting rest wavelength (2)1e-10minstr.bandwidthfloatnullablelambdaEnd[1221.7/2414.6]? Ending rest wavelength (2)1e-10minstr.bandwidthfloatnullable