J/ApJ/803/34 z~4-10 galaxies from HST legacy fields (Bouwens+, 2015) ================================================================================ UV luminosity functions at redshifts z~4 to z~10: 10000 galaxies from HST legacy fields. Bouwens R.J., Illingworth G.D., Oesch P.A., Trenti M., Labbe I., Bradley L., Carollo M., van Dokkum P.G., Gonzalez V., Holwerda B., Franx M., Spitler L., Smit R., Magee D. =2015ApJ...803...34B ================================================================================ ADC_Keywords: Surveys ; Galaxies, IR ; Redshifts ; Photometry, HST Keywords: galaxies: evolution; galaxies: high-redshift Abstract: The remarkable Hubble Space Telescope (HST) data sets from the CANDELS, HUDF09, HUDF12, ERS, and BoRG/HIPPIES programs have allowed us to map the evolution of the rest-frame UV luminosity function (LF) from z~10 to z~4. We develop new color criteria that more optimally utilize the full wavelength coverage from the optical, near-IR, and mid-IR observations over our search fields, while simultaneously minimizing the incompleteness and eliminating redshift gaps. We have identified 5859, 3001, 857, 481, 217, and 6 galaxy candidates at z~4, z~5, z~6, z~7, z~8, and z~10, respectively, from the ~1000arcmin^2^ area covered by these data sets. This sample of >10000 galaxy candidates at z>=4 is by far the largest assembled to date with HST. The selection of z~4-8 candidates over the five CANDELS fields allows us to assess the cosmic variance; the largest variations are at z>=7. Our new LF determinations at z~4 and z~5 span a 6 mag baseline and reach to -16 AB mag. These determinations agree well with previous estimates, but the larger samples and volumes probed here result in a more reliable sampling of >L_{star}_ galaxies and allow us to reassess the form of the UV LFs. Our new LF results strengthen our earlier findings to 3.4{sigma} significance for a steeper faint-end slope of the UV LF at z>4, with {alpha} evolving from {alpha}=-1.64+/-0.04 at z~4 to {alpha}=-2.06+/-0.13 at z~7 (and {alpha}=-2.02+/-0.23 at z~8), consistent with that expected from the evolution of the halo mass function. We find less evolution in the characteristic magnitude M^*^ from z~7 to z~4 the observed evolution in the LF is now largely represented by changes in {phi}_{star}_. No evidence for a non-Schechter-like form to the z~4-8 LFs is found. A simple conditional LF model based on halo growth and evolution in the M/L ratio ({alpha}(1+z}^-1.5^) of halos provides a good representation of the observed evolution. Description: The present determinations of the UV LFs at z~4-10 make use of essentially all the ultra-deep, wide-area observations obtained as part of the HUDF09+HUDF12 (Illingworth et al. 2013ApJS..209....6I), ERS, and CANDELS programs, in conjunction with archival HST observations over these fields. The pure-parallel observations from the BoRG/HIPPIES programs (Trenti et al. 2011ApJ...727L..39T; Yan et al. 2011ApJ...728L..22Y) are also utilized. Observations over these fields reach as deep as 30mag (5{sigma}), cover a total area of ~750arcmin^2^, and include deep coverage in at least six passbands from HST and Spitzer, from ~0.6 to 4.5um. A ~1000arcmin^2^ area is leveraged in total including the BoRG/HIPPIES program. File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- ReadMe 80 . This file table3.dat 62 10421 A complete list of the sources included in our z~4, z~5, z~6, z~7, z~8, and z~10 samples -------------------------------------------------------------------------------- See also: III/268 : DEEP2 Redshift Survey, Data Release 4 (Matthews+ 2013) II/319 : UKIDSS-DR9 LAS, GCS and DXS Surveys (Lawrence+ 2012) II/318 : GOODS Source Catalogs release r2.0z (Giavalisco+ 2008) II/284 : COSMOS Multi-Wavelength Photometry Catalog (Capak+, 2007) II/261 : GOODS initial results (Giavalisco+, 2004) J/A+A/570/A11 : The Hawk-I UDS and GOODS Survey (HUGS) (Fontana+, 2014) J/AJ/148/13 : Redshifts of 65 CANDELS supernovae (Rodney+, 2014) J/MNRAS/440/2810 : Galaxy luminosity function at z =~ 7 (Bowler+, 2014) J/ApJ/780/34 : H_160_-selected galaxies in the HUDF (Lundgren+, 2014) J/ApJS/207/24 : GOODS-S CANDELS multiwavelength catalog (Guo+, 2013) J/MNRAS/432/2696 : Galaxy luminosity function at z = 7-9 (McLure+, 2013) J/ApJS/206/10 : CANDELS multiwavelength catalog (Galametz+, 2013) J/ApJ/769/80 : Spitzer/IRAC observations of five deep fields (Ashby+, 2013) J/MNRAS/428/1128 : UDS/COSMOS HiZELS galaxies (Sobral+, 2013) J/ApJ/756/164 : UV galaxies in CANDELS from z=8 to z=4 (Finkelstein+, 2012) J/ApJ/754/83 : UV continuum for z~4-7 star-forming gal. (Bouwens+, 2012) J/A+A/544/A156 : UltraVISTA Catalogue Release DR1 (McCracken+, 2012) J/ApJ/742/111 : Extreme emission-line gal. in CANDELS (van der Wel+, 2011) J/ApJ/738/69 : SEDs of galaxies at 3.8~} 4 (Steidel+, 1999) J/MNRAS/300/303 : UV-selected galaxy redshift survey (Treyer+, 1998) Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 19 A19 --- ID Source identifier 21- 22 I2 h RAh Hour of Right Ascension (J2000) 24- 25 I2 min RAm Minute of Right Ascension (J2000) 27- 31 F5.2 s RAs Second of Right Ascension (J2000) 33 A1 --- DE- Sign of the Declination (J2000) 34- 35 I2 deg DEd Degree of Declination (J2000) 37- 38 I2 arcmin DEm Arcminute of Declination (J2000) 40- 43 F4.1 arcsec DEs Arcsecond of Declination (J2000) 45- 49 F5.2 mag F160W [22.5/31] Measured HST F160W-band AB magnitude (H_160_) 51- 52 I2 --- zset [4/10] Sample number (1) 54- 55 I2 --- dset [2/10] Data set number (2) 57- 61 F5.2 --- zphot [2.5/10.2] Photometric redshift as estimated by EAZY (3) 62 A1 --- f_zphot [*] redshift possibly lower (4) -------------------------------------------------------------------------------- Note (1): The mean redshift of the sample in which the source was found. Note (2): The data set from which the source was selected (see section 2 for further details): 1 = HUDF/XDF (Illingworth et al. 2013ApJS..209....6I); 2 = HUDF09-1 (Bouwens+, 2011ApJ...737...90B; 169 sources); 3 = HUDF09-2 (Bouwens+, 2011ApJ...737...90B; 990 sources); 4 = ERS (Windhorst et al. 2011ApJS..193...27W; 1134 sources); 5 = CANDELS GOODS-S (Grogin et al. 2011ApJS..197...35G; 2983 sources); 6 = CANDELS GOODS-N (Grogin et al. 2011ApJS..197...35G; 3919 sources); 7 = CANDELS UDS (Grogin et al. 2011ApJS..197...35G; 327 sources); 8 = CANDELS COSMOS (Grogin et al. 2011ApJS..197...35G; 392 sources); 9 = CANDELS EGS (Grogin et al. 2011ApJS..197...35G; 484 sources); 10 = BoRG/HIPPIES or other pure-parallel programs (23 sources). Note (3): Assumes that all sources are in the range z=2.5-11. Note (4): Higher Probability for Being at Low-Redshift. * = For a flat redshift prior, the EAZY photometric redshift code (Brammer et al. 2008ApJ...686.1503B) estimates that this source shows at least a 68% probability for having a redshift significantly lower than the nominal low-redshift limit for the nominal sample, i.e., z<2.5, z<3.5, z<4.4, z<5.4, z<6.3, and z<8 for candidate z~4, z~5, z~6, z~7, z~8, and z~10 galaxies, respectively. -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 03-Aug-2015