J/MNRAS/415/1479 LESS photometric redshift survey (Wardlow+, 2011)
The LABOCA survey of the Extended Chandra Deep Field-South:
a photometric redshift survey of submillimetre galaxies.
Wardlow J.L., Smail I., Coppin K.E.K., Alexander D.M., Brandt W.N.,
Danielson A.L.R., Luo B., Swinbank A.M., Walter F., Weiss A., Xue Y.Q.,
Zibetti S., Bertoldi F., Biggs A.D., Chapman S.C., Dannerbauer H.,
Dunlop J.S., Gawiser E., Ivison R.J., Knudsen K.K., Kovacs A., Lacey C.G.,
Menten K.M., Padilla N., Rix H.-W., Van Der Werf P.P.
<Mon. Not. R. Astron. Soc., 415, 1479-1508 (2011)>
=2011MNRAS.415.1479W 2011MNRAS.415.1479W
ADC_Keywords: Millimetric/submm sources ; Galaxies, IR ; Galaxies, photometry
Keywords: galaxies: evolution - galaxies: high-redshift - galaxies: starburst -
submillimetre: galaxies
Abstract:
We derive photometric redshifts from 17-band optical to mid-infrared
photometry of 78 robust radio, 24um and Spitzer IRAC counterparts to
72 of the 126 submillimetre galaxies (SMGs) selected at 870um by
LABOCA observations in the Extended Chandra Deep Field-South (ECDF-S).
We test the photometric redshifts of the SMGs against the extensive
archival spectroscopy in the ECDF-S.
Description:
SMGs typically have faint optical and near-IR counterparts (e.g.
Ivison et al. 2002MNRAS.337....1I 2002MNRAS.337....1I), so we require deep photometry for
accurate photometric redshift estimates. The ECDF-S was chosen for
this survey because it is an exceptionally well-studied field and as
such we are able to utilize data from extensive archival imaging and
spectroscopic surveys. For completeness and uniformity, we only
consider surveys that cover a large fraction of the ECDF-S rather than
the smaller and deeper central Chandra Deep Field-South (CDF-S)
region. Therefore, we utilize the MUltiwavelength Survey by Yale-Chile
(MUSYC; Gawiser et al. 2006, Cat. J/ApJS/162/1) near-IR survey for U-
to K-band imaging (Taylor et al. 2009, Cat. J/ApJS/183/295), and the
Spitzer IRAC/MUSYC Public Legacy in ECDF-S (SIMPLE) imaging for
Spitzer IRAC data (Damen et al. 2011, cat. J/ApJ/727/1). We also
include U-band data from the deep GOODS/VIMOS imaging survey of the
CDF-S (Nonino et al. 2009ApJS..183..244N 2009ApJS..183..244N); although this covers only
∼60 per cent of LESS SMGs, it is valuable for galaxies that are
undetected at short wavelengths in the shallower MUSYC survey.
In addition, we have carried out deep near-IR observations in the J
and Ks bands with the HAWK-I at the ESO-VLT (ID: 082.A-0890, PI: N.
Padilla).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 210 78 Observed photometry for robust counterparts to
LESS submillimetre galaxies (SMGs)
table3.dat 132 78 *The catalogue of 78 robust counterparts to
LESS submillimetre galaxies (SMGs)
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Note on table3.dat: their photometric redshift estimates, reduced χ2 of
the best-fitting SED and the number of photometric filters in which the
galaxy is observed. We also present the absolute rest-frame H-band magnitudes,
the derived FIR luminosities and characteristic dust temperatures of the SMGs.
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See also:
J/ApJ/707/1201 : LABOCA ECDFS Submillimeter Survey (LESS) (Weiss+, 2009)
J/MNRAS/413/2314 : submm galaxies radio and mid-IR counterpart (Biggs+, 2011)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [LESS]
6- 8 I3 --- LESS LESS sequential number (short name) (1)
9 A1 --- m_LESS [ab] Multiplicity index on Name
11 A1 --- l_UmagM Limit flag on UmagM (2)
12- 16 F5.2 mag UmagM ?=- MUSYC U magnitude
18- 21 F4.2 mag e_UmagM ? rms uncertainty on MUSYC U magnitude
23 A1 --- l_U38mag Limit flag on U38mag (2)
24- 28 F5.2 mag U38mag ?=- MUSYC U38 magnitude
30- 33 F4.2 mag e_U38mag ? rms uncertainty on MUSYC U38 magnitude
35 A1 --- l_UmagV Limit flag on UmagV (2)
36- 40 F5.2 mag UmagV ?=- VIMOS U magnitude
42- 45 F4.2 mag e_UmagV ? rms uncertainty on VIMOS U magnitude
47 A1 --- l_BmagV Limit flag on BmagV (2)
48- 52 F5.2 mag BmagV ?=- VIMOS B magnitude
54- 57 F4.2 mag e_BmagV ? rms uncertainty on VIMOS B magnitude
59 A1 --- l_VmagV Limit flag on VmagV (2)
60- 64 F5.2 mag VmagV ?=- VIMOS V magnitude
66- 69 F4.2 mag e_VmagV ? rms uncertainty on VIMOS V magnitude
71 A1 --- l_RmagV Limit flag on RmagV (2)
72- 76 F5.2 mag RmagV ?=- VIMOS R magnitude
78- 81 F4.2 mag e_RmagV ? rms uncertainty on VIMOS R magnitude
83 A1 --- l_ImagV Limit flag on ImagV (2)
84- 88 F5.2 mag ImagV ?=- VIMOS I magnitude
90- 93 F4.2 mag e_ImagV ? rms uncertainty on VIMOS I magnitude
95 A1 --- l_zmagV Limit flag on zmagV (2)
96-100 F5.2 mag zmagV ?=- VIMOS z magnitude
102-105 F4.2 mag e_zmagV ? rms uncertainty on VIMOS z magnitude
107 A1 --- l_JmagM Limit flag on JmagM (2)
108-112 F5.2 mag JmagM ?=- MUSYC J magnitude
114-117 F4.2 mag e_JmagM ? rms uncertainty on MUSYC J magnitude
119 A1 --- l_JmagH Limit flag on JmagH (2)
120-124 F5.2 mag JmagH ?=- HAWK-I J magnitude
126-129 F4.2 mag e_JmagH ? rms uncertainty on HAWK-I J magnitude
131 A1 --- l_HmagH Limit flag on HmagH (2)
132-136 F5.2 mag HmagH ?=- HAWK-I H magnitude
138-141 F4.2 mag e_HmagH ? rms uncertainty on HAWK-I H magnitude
143 A1 --- l_KmagM Limit flag on KmagM (2)
144-148 F5.2 mag KmagM ?=- MUSYC K magnitude
150-153 F4.2 mag e_KmagM ? rms uncertainty on MUSYC K magnitude
155 A1 --- l_KmagH Limit flag on KmagH (2)
156-160 F5.2 mag KmagH ?=- HAWK-I K magnitude
162-165 F4.2 mag e_KmagH ? rms uncertainty on HAWK-I K magnitude
167-171 F5.2 mag [3.6] ?=- Spitzer/IRAC 3.6um magnitude
173-176 F4.2 mag e_[3.6] ? rms uncertainty on IRAC 3.6um magnitude
178-182 F5.2 mag [4.5] ?=- Spitzer/IRAC 4.5um magnitude
184-187 F4.2 mag e_[4.5] ? rms uncertainty on IRAC 4.5um magnitude
189-193 F5.2 mag [5.8] Spitzer/IRAC 5.8um magnitude
195-198 F4.2 mag e_[5.8] rms uncertainty on IRAC 5.8um magnitude
200 A1 --- l_[8.0] Limit flag on 8.0um (2)
201-205 F5.2 mag [8.0] ?=- Spitzer/IRAC 8.0um magnitude
207-210 F4.2 mag e_[8.0] ? rms uncertainty on IRAC 8.0um magnitude
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Note (1): SMGs which are not covered by imaging in a given filter have no
photometry listed in that filter.
Note (2): 3σ limiting magnitudes are presented where sources are covered
by imaging but not detected.
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Byte-by-byte Description of file: table3.dat
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Bytes Format Units Label Explanations
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1- 4 A4 --- --- [LESS]
6- 21 A16 --- SMG LESS name (JHHMMSS.s+DDMMSS) (3)
23- 26 A4 --- --- [LESS]
28- 30 I3 --- LESS LESS sequential number (short name)
31 A1 --- m_LESS [ab] Multiplicity index on Name
33- 34 I2 h RAh Right ascension (J2000) (4)
36- 37 I2 min RAm Right ascension (J2000) (4)
39- 43 F5.2 s RAs Right ascension (J2000) (4)
45 A1 --- DE- Declination sign (J2000) (4)
46- 47 I2 deg DEd Declination (J2000) (4)
49- 50 I2 arcmin DEm Declination (J2000) (4)
52- 55 F4.1 arcsec DEs Declination (J2000) (4)
57- 60 F4.2 --- zph Photometric redshift (5)
62- 65 F4.2 --- E_zph Error on zph (upper value)
67- 70 F4.2 --- e_zph Error on zph (lower value)
72- 75 F4.1 --- chi2r Reduced chi2 value (6)
77- 78 I2 --- Nf Number of photometric filters in which each
SMG counterpart was detected
80- 81 I2 --- Nf2 Number of filters in which the SMG was
observed but not detected, providing a
limiting flux
84- 89 F6.2 mag HMAG Absolute magnitude in the rest-frame H band
91 A1 --- l_LFIR Limit flag on LFIR
92- 97 F6.2 TLsun LFIR FIR luminosity, in 1012L☉ (7)
99-104 F6.2 TLsun E_LFIR ? Error on LFIR (upper value)
106-111 F6.2 TLsun e_LFIR ? Error on LFIR (lower value)
112 A1 --- l_TD Limit flag on TD
113-117 F5.1 K TD Characteristic dust temperature (8)
119-122 F4.1 K E_TD ? Error on TD (upper value)
124-127 F4.1 K e_TD ? Error on TD (lower value)
129-130 A2 --- Type [RMI ] ID type (9)
132 A1 --- Note [*] Note on LESS 20 (10)
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Note (3): The SMG names correspond to those in Weiss et al. (2009,
Cat. J/ApJ/707/1201) and Biggs et al. (2011, Cat. J/MNRAS/413/2314).
Note (4): Coordinates are the J2000 position of the optical/near-IR counterpart.
Note (5): Since Hyperz was restricted to 0<z<7, the five galaxies whose upper
redshift limits yield a formal maximum redshift of zmax=7 are actually only
constrained in the lower redshift limit. Therefore, throughout this paper,
the redshifts of these galaxies are plotted as lower limits.
Note (6): Reduced χ2 of the best-fitting SED at the derived photometric
redshift.
Note (7): As discussed in Section 5.7, the FIR luminosity (LFIR) is derived from
the IR-radio correlation using the radio flux and the photometric redshift of
each SMG.
Note (8): The characteristic dust temperature (TD) is derived as discussed in
Section 5.7 from radio and submillimetre fluxes and the photometric redshift
of each SMG.
Note (9): ID types (see Biggs et al. 2011 Cat. J/MNRAS/413/2314for details)
as follows:
R = radio-identified counterpart
M = 24um-identified counterpart
I = IRAC-identified counterpart
Note (10): As shown in Section 5.1, LESS 20 appears to contain a radio-loud AGN.
Therefore, LFIR and TD presented here are likely significantly overestimated
due to the AGN contribution to the radio flux, as such LESS 20 is excluded
from our studies of the luminosity function, SFR and star formation history
of SMGs (Section 5.7).
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 27-Feb-2012