z ~ 7-10 Galaxies in the HUDF and GOODS Fields: UV Luminosity Functions

By R. Bouwens, G. Illingworth, M. Franx, H. C. Ford. 2008

248 citations recorded by the source corpus.

We use all available deep optical ACS and near-IR data over both the HUDF and the two GOODS fields to search for star-forming galaxies at z≳ 7 and constrain the UV LF within the first 700 Myr. Our data set includes ~23 arcmin2 of deep NICMOS J + H data and ~248 arcmin2 of ground-based (ISAAC+MOIRCS) data, coincident with ACS optical data of greater or equal depths. In total, we find eight ∼ 7.3 z-dropouts in our search fields, but no z ∼ 9 J-dropout candidates. A careful consideration of a wide variety of different contaminants suggest an overall contamination level of just ~12% for our z-dropout selection. After performing detailed simulations to accurately estimate the selection volumes, we derive constraints on the UV LFs at z ∼ 7 and z ∼ 9. For a faint-end slope α = − 1.74, our most likely values for MUV* and φ* at z ∼ 7 are –19.8 ± 0.4 mag and 1.1+ 1.7−0.7 × 10−3 Mpc−3, respectively. Our search results for z ∼ 9 J-dropouts set a 1 σ lower limit on MUV* of –19.6 mag assuming that φ* and α are the same as their values at slightly later times. This lower limit on MUV* is 1.4 mag fainter than our best-fit value at z ∼ 4, suggesting that the UV LF has undergone substantial evolution over this time period. No evolution is ruled out at 99% confidence from z ∼ 7 to z ∼ 6 and at 80% confidence from z ∼ 9 to z ∼ 7. We find that the mass-to-light ratio of halos evolves as ~(1 + z)−1 if we require that the observed brightening in MUV* with redshift [i.e., MUV* = (− 21.02 ± 0.09) + (0.36 ± 0.08) (z − 3.8) ] be consistent with the expected evolution in the halo mass function. Finally, we consider the shape of the UV LF at z≳ 5 and discuss the implications of the Schechter-like form of the observed LFs, particularly the unexpected abrupt cutoff at the bright end.

View Paper: https://www.semanticscholar.org/paper/ea7c69cd92d7cf0831b806b54ff8031939e55da0

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

1. R. Bouwens
2. P. Hopkins
3. P. Oesch
4. Richard S. Ellis
5. G. Illingworth
6. R. Dav'e
7. Brant Robertson
8. J. Dunlop

Citations in the corpus

• CLASH: THREE STRONGLY LENSED IMAGES OF A CANDIDATE z ≈ 11 GALAXY (2012, methodology): “Previous work (e.g., Bouwens et al. 2008, 2012b) has shown that dM∗/dz ∼ 0.3 yields good agreement to data at 4 . z .”
• GeV gamma-ray attenuation and the high-redshift UV background (2009, background): “Studies of UV luminosity functions of dropout galaxies by Bouwens and collaborators (Bouwens et al. 2008, 2007) find relatively low values for the global SFR, with a monotonic decrease above redshift four.”
• Signatures of X-rays in the early Universe (2012, background): “8 It is unlikely that Tvir is much greater than few×105 K, since these values approximately correspond to the faint end of the observed galaxy luminosity functions at z ∼ 6 (e.g. Bouwens et al. 2008; Labbe et al. 2010; Salvaterra et al. 2011; Finlator et al. 2011).”
• DISCOVERY OF z ∼ 8 GALAXIES IN THE HUBBLE ULTRA DEEP FIELD FROM ULTRA-DEEP WFC3/IR OBSERVATIONS (2009, methodology): “Using the Bouwens et al. (2008) LF parameterization as a guide, we fix α = −1.74, φ∗ = 0.0011 Mpc−3, and then derive confidence intervals on M∗UV .”
• Measurements of the UV background at 4.6 < z < 6.4 using the quasar proximity effect (2010, unknown): “2006; Bouwens et al. 2008; Ouchi et al. 2009).”
• THE MOST LUMINOUS z ∼ 9–10 GALAXY CANDIDATES YET FOUND: THE LUMINOSITY FUNCTION, COSMIC STAR-FORMATION RATE, AND THE FIRST MASS DENSITY ESTIMATE AT 500 Myr (2013, methodology): “In order to bridge the gap in wavelength range between the 1.6 μm probed by HST and the 3.6 μm covered by IRAC, we also made use of a deep K-band stack over GOODS-N from the multiobject infrared camera and spectrograph for Subaru (MOIRCS Kajisawa et al. 2006; Bouwens et al. 2008).”
• z ∼ 7 GALAXIES IN THE HUDF: FIRST EPOCH WFC3/IR RESULTS (2009, background): “While in previous studies only two galaxies were identified beyond a magnitude of 27.5, of which one is only marginally detected (Bouwens et al. 2008; Oesch et al. 2009a), the current WFC3 sample includes 11 such faint objects, resulting in much better constraints on the luminosity function at z ∼…”
• VERY BLUE UV-CONTINUUM SLOPE β OF LOW LUMINOSITY z ∼ 7 GALAXIES FROM WFC3/IR: EVIDENCE FOR EXTREMELY LOW METALLICITIES? (2009, background): “Such a large change could provide the needed photons to reionize the universe, providing a resolution to the current debate (e.g., Bouwens et al. 2008; Oesch et al. 2009a, 2009b; McLure et al. 2009; Bunker et al. 2009; Gonzalez et al. 2009; Ouchi et al. 2009; Pawlik et al. 2009).”
• UV CONTINUUM SLOPE AND DUST OBSCURATION FROM z ∼ 6 TO z ∼ 2: THE STAR FORMATION RATE DENSITY AT HIGH REDSHIFT (2009, methodology): “These dust-corrected SFR densities are somewhat lower than presented by Bouwens et al. (2008).”
• The luminosity function, halo masses and stellar masses of luminous Lyman-break galaxies at redshifts 5 < z < 6 (2008, background): “…luminosity function to reach<∼0.1L ⋆, and has therefore been crucial to constraining both the normalization and faintend slope of the luminosity function at3 < z < 6 (e.g. Dickinson et al. 2004; Malhotra et al. 2005; Oesch et al. 2007; Bouwens et al. 2006, 2007, 2008; Reddy et al. 2007).”
• New Measurements of the Ionizing Ultraviolet Background over 2 < z < 5 and Implications for Hydrogen Reionization (2013, background): “…> 6 indicate that the global star formation rate density declines steeply with redshift over 6 < z < 12 (e.g., Ouchi et al. 2009; Castellano et al. 2010; Bunker et al. 2010; Bouwens et al. 2006, 2008, 2011, 2012; Oesch et al. 2010; McLure et al. 2010, 2013; Schenker et al. 2013; Ellis et al. 2013).”
• Galaxies–intergalactic medium interaction calculation – I. Galaxy formation as a function of large-scale environment (2009, result): “The observational data for z 6 are uncertain and differ by up to a factor of 10 between different studies; compare, for example, the results of Bunker et al. (2006) and Bouwens et al. (2008).”
• THE STELLAR MASS DENSITY AND SPECIFIC STAR FORMATION RATE OF THE UNIVERSE AT z ∼ 7 (2009, methodology): “The solid line shows the redshift distribution that Bouwens et al. (2008) predict for the z-dropout selection.”
• Ubiquitous seeding of supermassive black holes by direct collapse (2012, methodology): “We normalise our free model parameter for the star formation efficiency against recent observations of the SFRD (Hopkins 2004; Mannucci 2007; Bouwens et al. 2008; Laporte et al. 2012).”
• THE GALAXY LUMINOSITY FUNCTION DURING THE REIONIZATION EPOCH (2010, methodology): “The LF evolution established from z ∼ 4 to z ∼ 6 (Bouwens et al. 2007) seems to continue into the dark ages, with progressively fewer bright sources (Bolton & Haehnelt 2007; Bouwens et al. 2008, 2010a; Oesch et al. 2009c).”
• On the origin of the galaxy star‐formation‐rate sequence: evolution and scatter (2009, background): “…rises by an order of magnitude to z 1 (e.g. Lilly et al. 1996; Schiminovich et al. 2005; Hopkins & Beacom 2006; Villar et al. 2008; Sobral et al. 2009), reaches a peak around z 2 and declines to higher redshifts (Madau, Pozzetti & Dickinson 1998; Bouwens et al. 2008; Pérez-González et al. 2008).”
• UV-CONTINUUM SLOPES AT z  ∼  4–7 FROM THE HUDF09+ERS+CANDELS OBSERVATIONS: DISCOVERY OF A WELL-DEFINED UV COLOR–MAGNITUDE RELATIONSHIP FOR z ⩾ 4 STAR-FORMING GALAXIES (2011, methodology): “We have utilized such techniques extensively in the last decade to establish the reliability of our selections, to quantify biases in measured magnitudes and colors, and to establish the needed corrections (e.g., Bouwens et al. 2003, 2004, 2006, 2007, 2008, 2009, 2011b).”