J/AJ/128/1ivo://CDS.VizieR/J/AJ/128/1doi:10.26093/cds/vizier.51280001CDSFadda D.Jannuzi B.T.Ford A.Storrie-Lombardi L.J.2023-04-06T16:51:06Z2005-08-26T13:49:01ZCDS support team

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

cds-question@unistra.frgalaxiesphotometryWe present R-band images covering more than 11 square degrees of sky that were obtained in preparation for the Spitzer Space Telescope First-Look Survey (FLS). The FLS was designed to characterize the mid-infrared sky at depths 2 orders of magnitude deeper than previous surveys. The extragalactic component is the first cosmological survey done with Spitzer. Source catalogs extracted from the R-band images are also presented. The R-band images were obtained using the Mosaic-1 camera on the 4m Mayall Telescope of the Kitt Peak National Observatory. Two relatively large regions of the sky were observed to modest depth: the main FLS extragalactic field (17h18m00s, +59{deg}30'00.0"[J2000]; l=88.3{deg}, b=+34.9{deg}) and the ELAIS-N1 field (16h10m01s, +54{deg}30'36.0"; l=84.2{deg}, b=+44.9{deg}). While both these fields were in early plans for the FLS, only a single deep-pointing test observation was made at the ELAIS-N1 location. The larger Legacy program SWIRE will include this region among its surveyed areas. The data products of our KPNO imaging (images and object catalogs) are made available to the community through the World Wide Web (via the Spitzer Science Center and NOAO Science Archive, http://ssc.spitzer.caltech.edu/fls/). The overall quality of the images is high. The measured positions of sources detected in the images have rms uncertainties in their absolute positions on the order of 0.35" with possible systematic offsets on the order of 0.1", depending on the reference frame of comparison. The relative astrometric accuracy is much better than 1/10 of an arcsecond. Typical delivered image quality in the images is 1.1" full width at half-maximum. The images are relatively deep, since they reach a median 5{sigma} depth limiting magnitude of R=25.5 (Vega) as measured within a 1.35 FWHM aperture, for which the signal-to-noise ratio (S/N) is maximal. Catalogs have been extracted with SExtractor, using thresholds in area and flux for which the number of false detections is below 1% at R=25. Only sources with S/N>3 have been retained in the final catalogs. Comparing the galaxy number counts from our images with those of deeper R-band surveys, we estimate that our observations are 50% complete at R=24.5. These limits in depth are sufficient to identify a substantial fraction of the infrared sources that will be detected by Spitzer. Use of the data: Use of these data must be accompanied by citation of the paper and acknowledgment: "The National Optical Astronomy Observatory (NOAO) is operated by the Association of Universities for Research in Astronomy (AURA), Inc. under cooperative agreement with the National Science Foundation."2004AJ....128....1Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/AJ/128/1CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-tohttp://ssc.spitzer.caltech.edu/fls/ : First Look Survey Home PageII/255 : SWIRE ELAIS N1 Source Catalogs (Surace+, 2004)J/A+A/424/371 : 1.4GHz First Look Survey (FLS) (Morganti+, 2004)J/AJ/125/2411 : SIRTF First-Look Survey (Condon+, 2003)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/AJ/128/1https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/AJ/128/1http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/AJ/128/1https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/AJ/128/1https://vizier.iucaa.in/viz-bin/votable?-source=J/AJ/128/1http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/AJ/128/1GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/AJ/128/1/table2 (Nominal coordinates of the observed subfields)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/128/1/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/128/1/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/128/1/table2?GETtext/xml+votable180.050000true259.450561.10.005555555555555556Cone search capability for table J/AJ/128/1/table5 (Properties of images and extracted catalogs)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/128/1/table5?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/128/1/table5?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/128/1/table5?GETtext/xml+votable180.050000true259.440416761.09558890.005555555555555556Cone search capability for table J/AJ/128/1/sources (All sources in the various fields)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/AJ/128/1/sources?https://vizier.iucaa.in/viz-bin/conesearch/J/AJ/128/1/sources?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/AJ/128/1/sources?GETtext/xml+votable180.050000true242.664853.491250.0055555555555555565/2538 2547 2553 6/10146-10147 10156 10158 10181-10183 10187 10192 10194 10200 10202 10209 10211 10217 10220-10221 10224 11521https://cdsarc.cds.unistra.fr/viz-bin/moc/J/AJ/128/1?format=asciiOpticaldefaultJ/AJ/128/1/table2Nominal coordinates of the observed subfieldsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintFieldField IDcharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainNobsNumber of 10 minute observationsintJ/AJ/128/1/table5Properties of images and extracted catalogsNstarNumber of stars (1)intrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSubfieldSubfield IDcharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainSeeingSeeing of the combined imagearcsecfloatRlim55 {sigma} limiting Cousins R magnitudemagfloatRlim33 {sigma} limiting Cousins R magnitudemagfloatNgalNumber of galaxies (1)intJ/AJ/128/1/sourcesAll sources in the various fieldsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSourceSource designation (based on J2000 position)charindexedRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainindexedDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainindexedRcmagAp? Aperture (3") R magnitude (Cousins)magfloatnullablee_RcmagAp? Error in RcmagApmagfloatnullableRcmagTotTotal R magnitude (Cousins)magfloate_RcmagTotError in RcmagTotmagfloatS/N? Signal-to-noise ratio of the detectionfloatnullableClassStellarity index computed by SExtractor (1)floatExtThe Galactic extinction, taken from Schlegel et al. (1998ApJ...500..525S)float