J/MNRAS/432/2696 Galaxy luminosity function at z = 7-9 (McLure+, 2013)
A new multifield determination of the galaxy luminosity function at z = 7-9
incorporating the 2012 Hubble ultra-deep field imaging.
McLure R.J., Dunlop J.S., Bowler R.A.A., Curtis-Lake E., Schenker M.,
Ellis R.S., Robertson B.E., Koekemoer A.M., Rogers A.B., Ono Y., Ouchi M.,
Charlot S., Wild V., Stark D.P., Furlanetto S.R., Cirasuolo M.,
Targett T.A.
<Mon. Not. R. Astron. Soc., 432, 2696-2716 (2013)>
=2013MNRAS.432.2696M 2013MNRAS.432.2696M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, photometry ; Redshifts
Keywords: galaxies: evolution - galaxies: formation - galaxies: high-redshift
Abstract:
We present a new determination of the ultraviolet (UV) galaxy
luminosity function (LF) at redshift z≃7 and 8, and a first
estimate at z≃9. An accurate determination of the form and
evolution of the galaxy LF during this era is of key importance for
improving our knowledge of the earliest phases of galaxy evolution and
the process of cosmic reionization. Our analysis exploits to the full
the new, deepest Wide Field Camera 3/infrared imaging from our
Hubble Space Telescope (HST) Ultra-Deep Field 2012 (UDF12)
campaign, with dynamic range provided by including a new and
consistent analysis of all appropriate, shallower/wider area HST
survey data. Our new measurement of the evolving LF at z≃7 to
8 is based on a final catalogue of ≃600 galaxies, and involves a
step-wise maximum-likelihood determination based on the photometric
redshift probability distribution for each object; this approach makes
full use of the 11-band imaging now available in the Hubble Ultra-Deep
Field (HUDF), including the new UDF12 F140W data, and the latest
Spitzer IRAC imaging. The final result is a determination of the z≃7
LF extending down to UV absolute magnitudes M1500=-16.75 (AB mag)
and the z≃8 LF down to M1500=-17.00. Fitting a Schechter function,
we find M1500*=-19.90+0.23_-0.28^,
logφ*=-2.96+0.18-0.23 and a faint-end slope
α=-1.90+0.14-0.15 at z≃7, and
M1500*=-20.12+0.37-0.48, logφ*=-3.35+0.28-0.47 and
α=-2.02+0.22-0.23 at z≃8. These results strengthen previous
suggestions that the evolution at z>7 appears more akin to 'density
evolution' than the apparent 'luminosity evolution' seen at z≃5-7. We
also provide the first meaningful information on the LF at z≃9,
explore alternative extrapolations to higher redshifts, and consider
the implications for the early evolution of UV luminosity density.
Finally, we provide catalogues (including derived zphot, M1500 and
photometry) for the most robust z∼6.5-11.9 galaxies used in this
analysis. We briefly discuss our results in the context of earlier
work and the results derived from an independent analysis of the UDF12
data based on colour-colour selection.
Description:
The data sets analysed in this paper form a 'wedding-cake'
structure ranging from the ultra-deep UDF12 observations covering an
area of only ~=4.5arcmin2 to wider area WFC3/IR survey data covering
several hundred arcmin2. Below we provide the basic observational
details of each data set in turn.
The data set which plays the pivotal role in constraining the faint
end of the galaxy LF at z≥7 and provides the primary motivation for
this paper is the new UDF12 WFC3/IR multiband imaging of the HUDF (GO
12498, P.I. Ellis).
To increase our ability to constrain the faint end of the
high-redshift LF we have also utilized the WFC3/IR imaging available
in the two parallel fields of the HUDF09 imaging campaign, hereafter
HUDF09-1 and HUDF09-2.
In addition to the HUDF and parallel fields, we have made extensive
use of the publicly available WFC3/IR imaging of the GOODS-S field
provided by CANDELS (Grogin et al., 2011ApJS..197...35G 2011ApJS..197...35G; Koekemoer et
al., 2011ApJS..197...36K 2011ApJS..197...36K).
In order to significantly increase the total areal coverage of our
data set, crucial for constraining the bright end of the z≥7 galaxy
LF, we have also analysed the publicly available CANDELS WFC3/IR+ACS
imaging in the UDS (Lawrence et al., 2007MNRAS.379.1599L 2007MNRAS.379.1599L, Cat.
II/314).
In order to increase our ability to constrain the bright end of the
z=8 LF, we have performed our own reduction and analysis (Bowler et
al., in preparation) of the data taken by the BoRG survey (Trenti et
al. 2011ApJ...727L..39T 2011ApJ...727L..39T, 2012ApJ...746...55T 2012ApJ...746...55T).
File Summary:
--------------------------------------------------------------------------------
FileName Lrecl Records Explanations
--------------------------------------------------------------------------------
ReadMe 80 . This file
tablea1.dat 105 100 Candidate z≥6.5 galaxies in the HUDF
tablea2.dat 85 100 Optical and near-IR photometry for the candidate
z≥6.5 galaxies in the HUDF
tablea3.dat 118 26 Candidate z≥6.5 galaxies in HUDF09-1
tablea4.dat 121 24 Candidate z≥6.5 galaxies in HUDF09-2
tablea6.dat 119 27 *Candidate z≥6.5 galaxies in CANDELS GS-DEEP
tablea7.dat 114 2 Candidate z≥6.5 galaxies in CANDELS GS-WIDE
tablea8.dat 95 7 Candidate z≥6.5 galaxies in CANDELS UDS
tablea5.dat 120 18 Candidate z≥6.5 galaxies in ERS
tablea9.dat 114 4 Candidate z≥6.5 galaxies in BoRG
refs.dat 64 19 References
--------------------------------------------------------------------------------
Note on tablea6.dat: Those objects which have significantly deeper z850 (F850LP)
limits lie within the footprint of the original HUDF ACS imaging.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea1.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- Name Name
17- 18 I2 h RAh Right ascension (J2000)
20- 21 I2 min RAm Right ascension (J2000)
23- 27 F5.2 s RAs Right ascension (J2000)
29 A1 --- DE- Declination sign (J2000)
30- 31 I2 deg DEd Declination (J2000)
33- 34 I2 arcmin DEm Declination (J2000)
36- 39 F4.1 arcsec DEs Declination (J2000)
41- 44 F4.1 --- zphot Best-fitting photometric redshift
46- 49 F4.1 --- b_zphot Lower value of 1σ photometric redshift
interval
50 A1 --- --- [-]
51- 54 F4.1 --- B_zphot Upper value of 1σ photometric redshift
interval
56- 60 F5.1 mag UVMAG Absolute UV magnitude, measured using a top-hat
filter at 1500Å in the rest frame of the
best-fitting galaxy SED template
62 A1 --- l_H160 Limit flag on H160
63- 66 F4.1 mag H160 Total apparent H160 (F160W) magnitude
(corrected to total assuming a point source)
68- 70 F3.1 mag E_H160 ? Error on H160 (upper value)
72- 74 F3.1 mag e_H160 ? Error on H160 (lower value)
76-105 A30 --- Ref References to previous discoveries of objects,
in refs.dat file
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea2.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 15 A15 --- Name Name
17 A1 --- l_z850 Limit flag on z850
18- 21 F4.1 mag z850 z850 (F850LP) magnitude (1)
23- 25 F3.1 mag E_z850 ? Error on z850 (upper value)
27- 29 F3.1 mag e_z850 ? Error on z850 (lower value)
31 A1 --- l_Y105 Limit flag on Y105
32- 35 F4.1 mag Y105 Apparent Y105 (F105W) magnitude (1)
37- 39 F3.1 mag E_Y105 ? Error on Y105 (upper value)
41- 43 F3.1 mag e_Y105 ? Error on Y105 (lower value)
45 A1 --- l_J125 Limit flag on J125
46- 49 F4.1 mag J125 Apparent J125 (F125W) magnitude (1)
51- 53 F3.1 mag E_J125 ? Error on J125 (upper value)
55- 57 F3.1 mag e_J125 ? Error on J125 (lower value)
59 A1 --- l_J140 Limit flag on J140
60- 63 F4.1 mag J140 Apparent J140 (F140W) magnitude (1)
65- 67 F3.1 mag E_J140 ? Error on J140 (upper value)
69- 71 F3.1 mag e_J140 ? Error on J140 (lower value)
73 A1 --- l_H160 Limit flag on H160
74- 77 F4.1 mag H160 Apparent H160 (F160W) magnitude (1)
79- 81 F3.1 mag E_H160 ? Error on H160 (upper value)
83- 85 F3.1 mag e_H160 ? Error on H160 (lower value)
--------------------------------------------------------------------------------
Note (1): In each case, the quoted photometry has been corrected to total
assuming a point source. Detections which are less significant than 2σ
are listed as the appropriate 2σ limit. All candidates are detected at
less than 2σ significance in the B435 (F435W), V606 (F606W) and
i775 (F775W) filters.
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea[3467].dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 14 A14 --- Name Name
16- 17 I2 h RAh Right ascension (J2000)
19- 20 I2 min RAm Right ascension (J2000)
22- 26 F5.2 s RAs Right ascension (J2000)
28 A1 --- DE- Declination sign (J2000)
29- 30 I2 deg DEd Declination (J2000)
32- 33 I2 arcmin DEm Declination (J2000)
35- 38 F4.1 arcsec DEs Declination (J2000)
40- 42 F3.1 --- zphot Best-fitting photometric redshift
44- 46 F3.1 --- b_zphot Lower value of 1σ photometric redshift
interval
47 A1 --- --- [-]
48- 50 F3.1 --- B_zphot Upper value of 1σ photometric redshift
interval
52- 56 F5.1 mag UVMAG Absolute UV magnitude, measured using a top-hat
filter at 1500Å in the rest frame of the
best-fitting galaxy SED template
58 A1 --- l_z850 Limit flag on z850
59- 62 F4.1 mag z850 Apparent z850 (F850LP) magnitude (corrected to
total assuming a point source) (1)
64- 66 F3.1 mag E_z850 ? Error on z850 (upper value)
68- 70 F3.1 mag e_z850 ? Error on z850 (lower value)
72 A1 --- l_Y105 Limit flag on Y105
73- 76 F4.1 mag Y105 Apparent Y105 (F105W) magnitude (corrected to
total assuming a point source) (1)
78- 80 F3.1 mag E_Y105 ? Error on Y105 (upper value)
82- 84 F3.1 mag e_Y105 ? Error on Y105 (lower value)
86 A1 --- l_J125 Limit flag on J125
87- 90 F4.1 mag J125 Apparent J125 (F125W) magnitude (corrected to
total assuming a point source) (1)
92- 94 F3.1 mag E_J125 ? Error on J125 (upper value)
96- 98 F3.1 mag e_J125 ? Error on J125 (lower value)
100 A1 --- l_H160 Limit flag on H160
101-104 F4.1 mag H160 Apparent H160 (F160W) magnitude (corrected to
total assuming a point source) (1)
106-108 F3.1 mag E_H160 ? Error on H160 (upper value)
110-112 F3.1 mag e_H160 ? Error on H160 (lower value)
114-121 A8 --- Ref References to previous discoveries of objects,
in refs.dat file
--------------------------------------------------------------------------------
Note (1): Detections which are less significant than 2σ are listed as the
appropriate 2σ limit (all candidates of tables A3 and A4 are detected
at less than 2σ significance in the V606 (F606W) and i775 (F775W) filters
and all candidates of tables A6 and A7 are detected at less than 2σ
significance in the B435 (F435W), V606 (F606W) and i775 (F775W) filters).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea8.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 14 A14 --- Name Name (1)
16- 17 I2 h RAh Right ascension (J2000)
19- 20 I2 min RAm Right ascension (J2000)
22- 26 F5.2 s RAs Right ascension (J2000)
28 A1 --- DE- Declination sign (J2000)
29- 30 I2 deg DEd Declination (J2000)
32- 33 I2 arcmin DEm Declination (J2000)
35- 38 F4.1 arcsec DEs Declination (J2000)
40- 42 F3.1 --- zphot Best-fitting photometric redshift
44- 46 F3.1 --- b_zphot Lower value of 1σ photometric
redshift interval
47 A1 --- --- [-]
48- 50 F3.1 --- B_zphot Upper value of 1σ photometric
redshift interval
52- 56 F5.1 mag UVMAG Absolute UV magnitude, measured using a top-hat
filter at 1500Å in the rest frame of the
best-fitting galaxy SED template
58 A1 --- l_i814 Limit flag on i814
59- 62 F4.1 mag i814 Apparent i814 (F814W) magnitude (corrected to
total assuming a point source) (2)
64- 67 F4.1 mag J125 Apparent J125 (F125W) magnitude (corrected to
total assuming a point source)(2)
69- 71 F3.1 mag E_J125 ? Error on J125 (upper value)
73- 75 F3.1 mag e_J125 ? Error on J125 (lower value)
77- 80 F4.1 mag H160 Apparent H160 (F160W) magnitude (corrected to
total assuming a point source)(2)
82- 84 F3.1 mag E_H160 ? Error on H160 (upper value)
86- 88 F3.1 mag e_H160 ? Error on H160 (lower value)
90- 95 A6 --- Ref References to previous discoveries of objects,
in refs.dat file
-------------------------------------------------------------------------------
Note (1): We note that CUDS_20114 is an extended, multicomponent, object
(Ouchi et al., 2009ApJ...696.1164O 2009ApJ...696.1164O), and that the photometry reported here
is for the central component only.
Note (2): Detections which are less significant than 2σ are listed as
the appropriate 2σ limit (all candidates are detected at less than
2σ significance in the V606 (F606W) filter).
-------------------------------------------------------------------------------
Byte-by-byte Description of file: tablea5.dat tablea9.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 14 A14 --- Name Name
16- 17 I2 h RAh Right ascension (J2000)
19- 20 I2 min RAm Right ascension (J2000)
22- 26 F5.2 s RAs Right ascension (J2000)
28 A1 --- DE- Declination sign (J2000)
29- 30 I2 deg DEd Declination (J2000)
32- 33 I2 arcmin DEm Declination (J2000)
35- 38 F4.1 arcsec DEs Declination (J2000)
40- 42 F3.1 --- zphot Best-fitting photometric redshift
44- 46 F3.1 --- b_zphot Lower value of 1σ photometric redshift
interval
47 A1 --- --- [-]
48- 50 F3.1 --- B_zphot Upper value of 1σ photometric redshift
interval
52- 56 F5.1 mag UVMAG Absolute UV magnitude, measured using a top-hat
filter at 1500Å in the rest frame of the
best-fitting galaxy SED template
58 A1 --- l_z850 Limit flag on z850
59- 62 F4.1 mag z850 ? Apparent z850 (F850LP) magnitude (corrected
to total assuming a point source) (1)
64- 66 F3.1 mag E_z850 ? Error on z850 (upper value)
68- 70 F3.1 mag e_z850 ? Error on z850 (lower value)
72 A1 --- l_Y098 Limit flag on Y098
73- 76 F4.1 mag Y098 Apparent Y098 (F098M) magnitude (corrected to
total assuming a point source) (1)
78- 80 F3.1 mag E_Y098 ? Error on Y098 (upper value)
82- 84 F3.1 mag e_Y098 ? Error on Y098 (lower value)
86 A1 --- l_J125 Limit flag on J125
87- 90 F4.1 mag J125 Apparent J125 (F125W) magnitude (corrected to
total assuming a point source) (1)
92- 94 F3.1 mag E_J125 ? Error on J125 (upper value)
96- 98 F3.1 mag e_J125 ? Error on J125 (lower value)
100-103 F4.1 mag H160 Apparent H160 (F160W) magnitude (corrected to
total assuming a point source) (1)
105-107 F3.1 mag E_H160 ? Error on H160 (upper value)
109-111 F3.1 mag e_H160 ? Error on H160 (lower value)
113-120 A8 --- Ref References to previous discoveries of objects,
in refs.dat file
--------------------------------------------------------------------------------
Note (1): Detections which are less significant than 2σ are listed as the
appropriate 2σ limit (all candidates in table A5 are detected at less
than 2σ significance in the B435 (F435W), V606 (F606W) and i775 (F775W)
filters, and all candidates in table A9 are detected at less than 2σ
significance in the V606 (F606W) or V600 (F600LP) filters).
--------------------------------------------------------------------------------
Byte-by-byte Description of file: refs.dat
--------------------------------------------------------------------------------
Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 2 I2 --- Ref Reference number
4- 22 A19 --- BibCode BibCode
24- 41 A18 --- Aut Author's name
43- 64 A22 --- Com Comments
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Jul-2015