SPECTROSCOPIC CONFIRMATION OF THREEz-DROPOUT GALAXIES ATz= 6.844-7.213: DEMOGRAPHICS OF Lyα EMISSION INz∼ 7 GALAXIES

Ono, Yoshiyasu; Ouchi, Masami; Mobasher, Bahram; Dickinson, Mark; Penner, K.; Shimasaku, Kazuhiro; Weiner, Benjamin J.; Kartaltepe, Jeyhan S.; Nakajima, Kengo; Nayyeri, Hooshang; Stern, Daniel; Kashikawa, Nobunari; Spinrad, Hyron

doi:10.1088/0004-637x/744/2/83

Cited by 410 publications

(607 citation statements)

References 105 publications

Supporting

Mentioning

560

Contrasting

Order By: Relevance

“…At 6.5 < z < 7.5, this feature is sampled by the large Z − Y color, as shown by a number of works using ground based imaging (Ouchi et al 2009;Castellano et al 2010a,b) and from space Mannucci et al 2007;Oesch et al 2009Oesch et al , 2010Bunker et al 2010;McLure et al 2010;Bouwens et al 2011). The spectroscopic confirmations of these candidates (shown in Fontana et al 2010;Vanzella et al 2011;Pentericci et al 2011;Stark et al 2011;Ono et al 2012) ensures that this technique is robust and the fraction of expected interlopers is quite low (less than 20% at z ∼ 6, as shown in Pentericci et al 2011).…”

Section: Selecting Galaxies At Z = 7: Color Criteriamentioning

confidence: 83%

“…The spectroscopic confirmations of the bright candidates in the GOODS fields, and in other ground based surveys, is currently ongoing (Fontana et al 2010;Stark et al 2011;Vanzella et al 2011;Ono et al 2012) and the fraction of lower-z interlopers seems to be less than 20% at z ∼ 6 ). Thus we are confident that the sample adopted for studying the size-luminosity relation in this paper is not heavily contaminated by lower-z galaxies.…”

Section: Is This Picture Conclusive?mentioning

confidence: 87%

See 1 more Smart Citation

The size-luminosity relation atz = 7 in CANDELS and its implication on reionization

Grazian

Castellano

Fontana

et al. 2012

A&A

101

157

View full text Add to dashboard Cite

Context. The exploration of the relation between galaxy sizes and other physical parameters (luminosity, mass, star formation rate) has provided important clues for understanding galaxy formation, but such exploration has until recently been limited to intermediate redshift objects. Aims. We use the currently available CANDELS Deep+Wide surveys in the GOODS-South, UDS and EGS fields, complemented by data from the HUDF09 program, to address the relation between size and luminosity at z ∼ 7. Methods. The six different fields used for this study are characterized by a wide combination of depth and areal coverage, well suited for reducing the biases on the observed size-magnitude plane. From these fields, we select 153 z-band dropout galaxies. Detailed simulations have been carried out for each of these six fields, inserting simulated galaxies at different magnitudes and half light radius in the two dimensional images for all the Hubble Space Telescope (HST) bands available and recovering them as carried out for the real galaxies. These simulations allow us to derive precisely the completeness as a function of size and magnitude and to quantify measurements errors/biases, under the assumption that the 2D profile of z = 7 galaxies is well represented by an exponential disk function. Results. We find in a rather robust way that the half light radius distribution function of z ∼ 7 galaxies fainter than J = 26.6 is peaked at ≤0.1 arcsec (or equivalently 0.5 kpc proper), while at brighter magnitudes high-z galaxies are typically larger than ∼0.15 arcsec. We also find a well defined size-luminosity relation, Rh ∝ L 1/2 . We compute the luminosity function (LF) in the HUDF and P12HUDF fields, finding large spatial variation on the number density of faint galaxies. Adopting the size distribution and the size-luminosity relation found for faint galaxies at z = 7, we derive a mean slope of −1.7 ± 0.1 for the LF of LBGs at this redshift. Conclusions. Using this LF, we find that the number of ionizing photons emitted from galaxies at z ∼ 7 cannot keep the Universe re-ionized if the IGM is clumpy (C HII ≥ 3) and the Lyman continuum escape fraction of high-z LBGs is relatively low ( f esc ≤ 0.3). If these results are confirmed and strengthened by future CANDELS data, in particular by the forthcoming deep observations in GOODS-South and North and the wide field COSMOS, we can put severe limits to the role of galaxies in the reionization of the Universe.

show abstract

Section: Selecting Galaxies At Z = 7: Color Criteriamentioning

confidence: 83%

Section: Is This Picture Conclusive?mentioning

confidence: 87%

The size-luminosity relation atz = 7 in CANDELS and its implication on reionization

Grazian

Castellano

Fontana

et al. 2012

A&A

101

157

View full text Add to dashboard Cite

show abstract

“…At z ∼ 7 Ono et al (2012), Pentericci et al (2011), andSchenker et al (2012) all find that the fraction decreases from z ∼ 6 to z ∼ 7. Currently, there is a factor of two discrepancy between the fraction of luminous dropout sources with EW Lyα,0 > 25 Å at z ∼ 6 (Curtis-Lake et al 2012; Stark et al 2010).…”

Section: Fraction Of Lbgs With Lyαmentioning

confidence: 93%

Lyα EMISSION FROM HIGH-REDSHIFT SOURCES IN COSMOS

Mallery

Mobasher

Capak

et al. 2012

ApJ

Self Cite

View full text Add to dashboard Cite

We investigate spectroscopically measured Lyα equivalent widths (EWs) and escape fractions of 244 sources of which 95 are Lyman break galaxies (LBGs) and 106 Lyman alpha emitters (LAEs) at z ∼ 4.2, z ∼ 4.8, and z ∼ 5.6 selected from intermediate and narrowband observations. The sources were selected from the Cosmic Evolution Survey and observed with the DEIMOS spectrograph. We find that the distribution of EWs shows no evolution with redshift for both the LBG selected sources and the intermediate/narrowband LAEs. We also find that the Lyα escape fraction of intermediate/narrowband LAEs is on average higher and has a larger variation than the escape fraction of LBG selected sources. The escape fraction does not show a dependence with redshift. Similar to what has been found for LAEs at low redshifts, the sources with the highest extinctions show the lowest escape fractions. The range of escape fractions increases with decreasing extinction. This is evidence that the dust extinction is the most important factor affecting the escape of Lyα photons, but at low extinctions other factors, such as the H i covering fraction and gas kinematics, can be just as effective at inhibiting the escape of Lyα photons.

show abstract

“…The faintest sources are detected in three ALMA data sets taken by Maiolino et al (2015), who targeted three Lyα emitters at z ∼ 6-7: BDF-3299, BDF-521 and SDF-46975 (Vanzella et al 2011;Ono et al 2012). The BDF-3299 data (field a in Table 1) were observed during two different epochs: a first observation between October and November 2013 and a second one in April 2014.…”

Section: Observations and Data Reductionmentioning

confidence: 99%

ALMA constraints on the faint millimetre source number counts and their contribution to the cosmic infrared background

Carniani

Maiolino

Zotti

et al. 2015

A&A

126

View full text Add to dashboard Cite

We have analysed 18 ALMA continuum maps in Bands 6 and 7, with rms down to 7.8 µJy, to derive differential number counts down to 60 µJy and 100 µJy at λ = 1.3 mm and λ = 1.1 mm, respectively. Furthermore, the non-detection of faint sources in the deepest ALMA field enabled us to set tight upper limits on the number counts down to 30 µJy. This is a factor of four deeper than the currently most stringent upper limit. The area covered by the combined fields is 9.5 × 10 −4 deg 2 at 1.1 mm and 6.6 × 10 −4 deg 2 at 1.3 mm. With respect to previous works, we improved the source extraction method by requiring that the dimension of the detected sources be consistent with the beam size. This method enabled us to remove spurious detections that have plagued the purity of the catalogues in previous studies. We detected 50 faint sources (at fluxes <1 mJy) with signal-to-noise (S/N) >3.5 down to 60 µJy, hence improving the statistics by a factor of four relative to previous studies. The inferred differential number counts are dN/d(Log 10 S ) = 1 × 10 5 deg 2 at a 1.1 mm flux S λ = 1.1 mm = 130 µJy, and dN/d(Log 10 S ) = 1.1×10 5 deg 2 at a 1.3 mm flux S λ = 1.3 mm = 60 µJy. At the faintest flux limits probed by our data, i.e. 30 µJy and 40 µJy, we obtain upper limits on the differential number counts of dN/d(Log 10 S ) < 7 × 10 5 deg 2 and dN/d(Log 10 S ) < 3×10 5 deg 2 , respectively. Determining the fraction of cosmic infrared background (CIB) resolved by the ALMA observations was hampered by the large uncertainties plaguing the CIB measurements (a factor of four in flux). However, our results provide a new lower limit to CIB intensity of 17.2 Jy deg −2 at 1.1 mm and of 12.9 Jy deg −2 at 1.3 mm. Moreover, the flattening of the integrated number counts at faint fluxes strongly suggests that we are probably close to the CIB intensity. Our data imply that galaxies with star formation rate (SFR) < 40 M /yr certainly contribute less than 50% to the CIB (and probably a much lower percentage) while more than 50% of the CIB must be produced by galaxies with SFR > 40 M /yr. The differential number counts are in nice agreement with recent semi-analytical models of galaxy formation even as low as our faint fluxes. Consequently, this supports the galaxy evolutionary scenarios and assumptions made in these models.

show abstract

SPECTROSCOPIC CONFIRMATION OF THREEz-DROPOUT GALAXIES ATz= 6.844-7.213: DEMOGRAPHICS OF Lyα EMISSION INz∼ 7 GALAXIES

Cited by 410 publications

References 105 publications

The size-luminosity relation atz = 7 in CANDELS and its implication on reionization

The size-luminosity relation atz = 7 in CANDELS and its implication on reionization

Lyα EMISSION FROM HIGH-REDSHIFT SOURCES IN COSMOS

ALMA constraints on the faint millimetre source number counts and their contribution to the cosmic infrared background

Contact Info

Product

Resources

About