J/MNRAS/418/2074 Robust sample of galaxies at 6.0<z<8.7 (Mclure+, 2011)
A robust sample of galaxies at redshifts 6.0<z<8.7: stellar populations,
star formation rates and stellar masses.
Mclure R.J., Dunlop J.S., De Ravel L., Cirasuolo M., Ellis R.S.,
Schenker M., Robertson B.E., Koekemoer A.M., Stark D.P., Bowler R.A.A.
<Mon. Not. R. Astron. Soc., 418, 2074-2105 (2011)>
=2011MNRAS.418.2074M 2011MNRAS.418.2074M
ADC_Keywords: Galaxy catalogs ; Redshifts ; Photometry, infrared
Keywords: galaxies: evolution - galaxies: formation - galaxies: high-redshift
Abstract:
We present the results of a photometric redshift analysis designed to
identify z≥6 galaxies from the near-infrared Hubble Space Telescope
imaging in three deep fields [Hubble Ultra Deep Field (HUDF), HUDF09-2
and Early Release Science] covering a total area of 45 square arcmin.
By adopting a rigorous set of criteria for rejecting low-redshift
interlopers, and by employing a deconfusion technique to allow the
available ultradeep IRAC imaging to be included in the
candidate-selection process, we have derived a robust sample of 70
Lyman break galaxies (LBGs) spanning the redshift range 6.0<z<8.7.
Description:
The analysis in this paper relies on the publicly available optical,
near-IR and mid-IR imaging data covering the HUDF, HUDF09-2 and ERS
field.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
sample.dat 99 73 Details of the final high-redshift sample in
the HUDF, ERS field and HUDF09-2 (tables 2-4)
table6.dat 104 21 The best-fitting parameters returned by our
SED-fitting analysis of the 21 objects in our
final robust sample with detections at
either 3.6 or 3.6+4.5um
phot.dat 156 73 Basic observational properties of the final
high-redshift galaxy sample in the HUDF,
ERS field and HUDF09-2 (tables B1-B3)
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See also:
J/ApJ/653/53 : z∼6 galaxies UV luminosity function (Bouwens+, 2006)
J/ApJ/668/839 : 1308 HUDF galaxies spectrophotometric redshifts (Ryan+, 2009)
J/AJ/141/14 : HST WFC3 ERS : emission-line galaxies (Straughn+, 2011)
Byte-by-byte Description of file: sample.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Name Name (G1)
15- 16 I2 h RAh Right ascension (J2000)
18- 19 I2 min RAm Right ascension (J2000)
21- 25 F5.2 s RAs Right ascension (J2000)
27 A1 --- DE- Declination sign (J2000)
28- 29 I2 deg DEd Declination (J2000)
31- 32 I2 arcmin DEm Declination (J2000)
34- 37 F4.1 arcsec DEs Declination (J2000)
39- 42 F4.2 --- zph Photometric Redshift
44- 47 F4.2 --- b_zph Lower value of redshift interval
48 A1 --- --- [-]
49- 52 F4.2 --- B_zph Upper value of redshift interval
54- 56 F3.1 --- chi2 Value of χ2 for the best-fitting
SED template
58- 62 F5.1 --- Dchi2 Difference in χ2 (1)
64- 68 F5.1 mag M1500 Absolute magnitude of the best-fitting SED
template (2)
70- 73 F4.1 --- beta UV spectral slope (3)
75- 77 F3.1 --- e_beta rms uncertainty on beta
79- 82 F4.2 --- zLya Best-fitting photometric redshift derived
including Lymanα emission as an
additional free parameter
84- 87 F4.1 [10-7W] logLya ?=- logarithm of luminosity of corresponding
best-fitting Lyman-α emission line
89- 99 A11 --- Lit Results of cross-checking each candidate
against existing literature studies of the
WFC3/IR data in the HUDF (table2),
ERS (table3) or HUDF09-2 (table) fields (4)
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Note (1): Difference in χ2 between the best-fitting high-redshift SED
template and the alternative photometric redshift solution at low redshift
(typically at 1.0<zphot<2.5)
Note (2): where M1500 is measured using a 100Å-wide filter centred on a
rest-frame wavelength of 1500Å.
Note (3): UV spectral slope (f(λ)∝λβ),
derived using the formulae listed in Section 4.
Note (4): Matches were found with the following papers:
M = McLure et al. (2010MNRAS.403..960M 2010MNRAS.403..960M)
B = Bouwens et al. (2011ApJ...737...90B 2011ApJ...737...90B); robust
Bp = Bouwens et al. (2011ApJ...737...90B 2011ApJ...737...90B); potential
F = Finkelstein et al. (2010ApJ...719.1250F 2010ApJ...719.1250F)
W = Wilkins et al. (2011MNRAS.411...23W 2011MNRAS.411...23W)
Y = Yan et al. (2010RAA....10..867Y 2010RAA....10..867Y)
L = Lorenzoni et al. (2011MNRAS.414.1455L 2011MNRAS.414.1455L)
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Byte-by-byte Description of file: table6.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Name Name (G1)
15- 19 A5 --- SFH Best-fitting Star Formation History (1)
21- 24 F4.2 Sun Z Best-fitting SED template metallicity
26- 28 I3 Myr Age Best-fitting SED template age (2)
30- 32 F3.1 mag AV Best-fitting SED template reddening
34- 37 F4.1 10+9Msun M* Best-fitting SED template stellar mass
39- 41 F3.1 10+9Msun E_M* Error on M* (upper value)
43- 46 F4.1 10+9Msun e_M* Error on M* (lower value)
48- 51 F4.1 Msun/yr SFR Best-fitting SED template star formation
rate (3)
53- 56 F4.1 Msun/yr E_SFR Error on SFR (upper value)
58- 61 F4.1 Msun/yr e_SFR Error on SFR (lower value)
63- 65 F3.1 --- chi2b Best-fitting SED template {chi2} value
67- 70 F4.1 --- chi2c Best-fitting Constant-Star-Forming (CSF) model
with Z=0.2Z☉ and AV=0.0 {chi2} value
71 A1 --- n_chi2c [*] Note on chi2c (4)
73- 75 I3 Myr Ageb Best-fitting CSF model with Z=0.2Z☉ and
AV=0.0 age (2)
77- 79 F3.1 10+9Msun M*b Best-fitting CSF model with Z=0.2Z☉ and
AV=0.0 stellar mass
81- 83 F3.1 10+9Msun E_M*b Error on M*b (upper value)
85- 87 F3.1 10+9Msun e_M*b Error on M*b (lower value)
89- 91 F3.1 Msun/yr SFRb Best-fitting CSF model with Z=0.2Z☉ and
AV=0.0 star formation rate
93- 95 F3.1 Msun/yr E_SFRb Error on SFRb (upper value)
97- 99 F3.1 Msun/yr e_SFRb Error on SFRb (lower value)
101-104 F4.1 Msun/yr SFRuv Estimate of the SFR based on the UV
luminosity (M1500) (5)
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Note (1): which is either an instantaneous burst (B), C (Const) or
exponentially decaying (E) star formation rate.
For those objects where the best-fitting SFH is exponentially decaying
[i.e. SFR∝exp(-t/τ)], the proceeding number indicates the
characteristic star-formation time-scale in Gyr (i.e. E0.2=>τ=0.2Gyr).
Note (3): For those objects where the best-fitting SFH is Burst, the SFR listed
is derived from the best-fitting model with a constant or exponentially
decaying SFH.
Note (2): Ages listed refer to the total age of the system, rather than a
luminosity-weighted age.
Note (4): * for objects rejected because their best-fitting SED templates have
an unacceptably high χ2.
Note (5): with no correction for dust attenuation, which has been derived using
the Madau, Pozzetti & Dickinson (1998ApJ...498..106M 1998ApJ...498..106M) formula
(corrected to a Chabrier IMF).
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Byte-by-byte Description of file: phot.dat
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Bytes Format Units Label Explanations
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1- 13 A13 --- Name Name (G1)
15- 16 I2 h RAh Right ascension (J2000)
18- 19 I2 min RAm Right ascension (J2000)
21- 25 F5.2 s RAs Right ascension (J2000)
27 A1 --- DE- Declination sign (J2000)
28- 29 I2 deg DEd Declination (J2000)
31- 32 I2 arcmin DEm Declination (J2000)
34- 37 F4.1 arcsec DEs Declination (J2000)
39 A1 --- l_i775 Limit flag on i775
40- 44 F5.2 mag i775 i775 magnitude (1)
46- 49 F4.2 mag E_i775 ? Error on i775 (upper value)
51- 54 F4.2 mag e_i775 ? Error on i775 (lower value)
56 A1 --- l_Z850 Limit flag on Z850
57- 61 F5.2 mag Z850 Z850 magnitude
63- 66 F4.2 mag E_Z850 ? Error on Z850 (upper value)
68- 71 F4.2 mag e_Z850 ? Error on Z850 (lower value)
73 A1 --- l_Y105 Limit flag on Y105
74- 78 F5.2 mag Y105 Y105 (HUDF) or Y098 (ERS) magnitude (1)
80- 83 F4.2 mag E_Y105 ? Error on Y105 (upper value)
85- 88 F4.2 mag e_Y105 ? Error on Y105 (lower value)
90 A1 --- l_J125 Limit flag on J125
91- 95 F5.2 mag J125 J125 magnitude (1)
97-100 F4.2 mag E_J125 ? Error on J125 (upper value)
102-105 F4.2 mag e_J125 ? Error on J125 (lower value)
107 A1 --- l_H160 Limit flag on H160
108-112 F5.2 mag H160 H160 magnitude (1)
114-117 F4.2 mag E_H160 ? Error on H160 (upper value)
119-122 F4.2 mag e_H160 ? Error on H160 (lower value)
124 A1 --- l_IRAC1 Limit flag on IRAC1
125-129 F5.2 mag IRAC1 ? IRAC1 magnitude (3.6um) (1)
131-134 F4.2 mag E_IRAC1 ? Error on IRAC1 (upper value)
136-139 F4.2 mag e_IRAC1 ? Error on IRAC1 (lower value)
141 A1 --- l_IRAC2 Limit flag on IRAC2
142-146 F5.2 mag IRAC2 ? IRAC2 magnitude (4.5um) (1)
148-151 F4.2 mag E_IRAC2 ? Error on IRAC2 (upper value)
153-156 F4.2 mag e_IRAC2 ? Error on IRAC2 (lower value)
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Note (1): Photometry of each candidate, as measured in a 0.6-arcsec-diameter
aperture. The magnitudes listed here are derived from the actual fluxes used
in the SED fitting and are not corrected to total, but have been corrected
for galactic extinction and the relative aperture losses between the ACS and
WFC3/IR. All candidates are undetected in filters at shorter wavelengths than
i775, and all detections which are significant at less than the 2σ level
are listed as 2σ upper limits. It should be noted that because the IRAC
photometry is derived via a deconfusion process, the uncertainties and
2σ limits are highly position-dependent.
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Global notes:
Note (G1): Galaxies identified as HUDF_NNNN, ERS_NNNNN and HUDF09-2_NNN.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 30-Jul-2012