J/A+A/477/55 ACO 1825 and AC 114 EROs photometry (Hempel+, 2008)
EROs found behind lensing clusters.
II. Empirical properties, classification, and SED modelling based on
multi-wavelength observations.
Hempel A., Schaerer D., Egami E., Pello R., Wise M., Richard J.,
Le Borgne J.-F., Kneib J.-P.
<Astron. Astrophys., 477, 55-66 (2008)>
=2008A&A...477...55H 2008A&A...477...55H
ADC_Keywords: Clusters, galaxy ; Galaxies, photometry ; Photometry, infrared
Keywords: galaxies: high-redshift - galaxies: starburst - infrared: galaxies -
galaxies: evolution
Abstract:
We study the properties and nature of extremely red galaxies (ERO,
R-K≥5.6) found behind two lensing clusters and compare them with
other known galaxy populations. New HST/ACS, Spitzer (IRAC and MIPS),
and Chandra/ACIS observations of the two lensing clusters Abell 1835
and AC 114 (ACCG 114) have been obtained, combined with our earlier
optical and near-IR observations and used to study EROs in these deep
fields.
Description:
New z-band (F850LP, denoted z850 hereafter) imaging was obtained with
the ACS camera onboard HST in November 2004 (AC114) and July 2005
(Abell 1835). The 3.6, 4.5, 5.8, and 8.0µm images were obtained
using the Infrared Array Camera (IRAC), while the 24µm images were
obtained using the Multi-band Imaging Photometer for Spitzer (MIPS),
both onboard the Spitzer Space Telescope. Both Abell 1835 and AC114
were observed previously by Chandra.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tab23.dat 140 22 Optical and NIR photometry of EROs in Abell 1835
(13 objects) and in AC 114 (9 objects)
tab456.dat 127 20 IRAC and MIPS fluxes (table4), X-ray flux limits
(table5) and magnification factors µ from the
lensing models predicted for various source
redshifts zs (table6) for the EROs in
Abell 1835 and AC114
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See also:
J/MNRAS/330/1 : HST observations of Extremely Red Objects (Smith+, 2002)
J/ApJ/581/844 : Radio and Infrared observations of EROs (Smail+, 2002)
J/MNRAS/346/1125 : IK photometry of faint Extremely Red Objects (Gilbank+ 2003)
J/PASJ/55/1079 : BVRi'z'JHKs photometry of ERO objects (Miyazaki+, 2003)
J/MNRAS/361/525 : Las Campanas Infrared Survey. V. (Doherty+, 2005)
J/ApJ/627/621 : Catalog of Extremely Red Objects (Sawicki+, 2005)
J/A+A/432/69 : Extremely Red Objects XMM-Newton observations (Brusa+, 2005)
Byte-by-byte Description of file: tab23.dat
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Bytes Format Units Label Explanations
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1- 8 A8 --- Cluster Cluster name (ACO 1835 or AC 114)
10- 13 I4 --- [HSE2008] Identification number,
[HSE2008] Cluster NNNN in Simbad
14 A1 --- f_[HSE2008] [a] Flag for objects that appear twice
because of multiple ACS detections
15 A1 --- n_[HSE2008] [*] 1σ detection (1)
17- 18 I2 --- [RPS2006] ? Identification number in Richard et al.
(2006A&A...456..861R 2006A&A...456..861R),
[RPS2006] Cluster NN in Simbad
20- 21 I2 h RAh Right ascension (J2000)
23- 24 I2 min RAm Right ascension (J2000)
26- 31 F6.3 s RAs Right ascension (J2000)
33 A1 --- DE- Declination sign (J2000)
34- 35 I2 deg DEd Declination (J2000)
37- 38 I2 arcmin DEm Declination (J2000)
40- 44 F5.2 arcsec DEs Declination (J2000)
46 A1 --- l_Vmag Limit flag on Vmag
47- 50 F4.1 mag Vmag 3σ V magnitude (2)
52 A1 --- l_Rmag Limit flag on Vmag
53- 57 F5.2 mag Rmag R magnitude
58 A1 --- n_Rmag [ab] Note on Rmag (3)
59- 62 F4.2 mag e_Rmag ? rms uncertainty on Rmag
64 A1 --- l_Imag Limit flag on Imag (2)
65- 69 F5.2 mag Imag ? I magnitude
70 A1 --- n_Imag [c] Note on Imag (3)
71- 74 F4.2 mag e_Imag ? rms uncertainty on Imag
76 A1 --- l_z850mag Limit flag on z850mag (2)
77- 81 F5.2 mag z850mag z850 magnitude
83- 86 F4.2 mag e_z850mag ? rms uncertainty on z850mag
88 A1 --- l_SZmag Limit flag on SZmag (2)
89- 93 F5.2 mag SZmag ? 3σ SZ (1.05um) magnitude
95- 98 F4.2 mag e_SZmag ? rms uncertainty on SZmag
100 A1 --- l_Jmag Limit flag on Jmag (2)
101-105 F5.2 mag Jmag 3σ J magnitude
107-110 F4.2 mag e_Jmag ? rms uncertainty on Jmag
112-116 F5.2 mag Hmag H magnitude (4)
118-121 F4.2 mag e_Hmag rms uncertainty on Hmag (4)
123-127 F5.2 mag Ksmag Ks magnitude (4)
129-132 F4.2 mag e_Ksmag rms uncertainty on KsHmag (4)
134-136 A3 --- DRG [yes no] DRG criterion (J-K>2.3) satisfied
138-140 A3 --- IERO [yes no ND] Classified as IERO (5)
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Note (1): * for EROs listed in Richard et al. (2006A&A...456..861R 2006A&A...456..861R) and
Schaerer et al. (2007A&A...469...47S 2007A&A...469...47S) based on a 1σ detection
threshold in the used R-band
Note (2): 3σ limit magnitudes:
----------------------------------------
Band ACO 1834 AC 114
----------------------------------------
V = 26.9 27.3
R = 26.6 27.7 or 24.9
I = 25.5 25.6
z850 = 26.5 ---
SZ = 27.5 ---
J = 24.4 ---
----------------------------------------
Note (3): Notes as follows:
a = Since the effective exposure time is lower in this region, a
lower detection limit has been applied (cf. Sect. 4.1)
b = Object located where two regions with different exposure times
meet. The detection limit for the shorter exposure was adopted
(see Sect. 4.1 for more details)
c = Object lies outside of image
Note (4): The magnitude errors given here are solely based on the
Sextractor output and are likely underestimated (cf. text).
Errors of 0.00 occur due to rounding effects.
Note (5): Several objects can be classified as IERO as described by Yan et
al. (2004ApJ...616...63Y 2004ApJ...616...63Y) (fν(3.6um)/fν(z850)>20).
ND stand for no data available, possibly due to blending
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Byte-by-byte Description of file: tab456.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 8 A8 --- Cluster Cluster name (ACO 1835 or AC 114)
10- 13 I4 --- [HSE2008] Identification number,
[HSE2008] Cluster NNNN in Simbad
15- 16 I2 --- [RPS2006] ? Identification number in Richard et al.
(2006A&A...456..861R 2006A&A...456..861R),
[RPS2006] Cluster NN in Simbad
18- 22 F5.1 uJy F3.6um ? Flux at 3.6um
23 A1 --- f_F3.6um [b] b for blended
24- 26 F3.1 uJy e_F3.6um ? rms uncertainty on F3.6um
28- 32 F5.1 uJy F4.5um ? Flux at 4.5um
33 A1 --- f_F4.5um [b] b for blended
34- 36 F3.1 uJy e_F4.5um ? rms uncertainty on F4.5um
38 A1 --- l_F5.8um Limit flag on F5.8um
39- 43 F5.1 uJy F5.8um ? Flux at 5.8um
44 A1 --- f_F5.8um [b] b for blended
45- 47 F3.1 uJy e_F5.8um ? rms uncertainty on F5.8um
49 A1 --- l_F8.0um Limit flag on F8.0um
50- 53 F4.1 uJy F8.0um ? Flux at 8.0um
54 A1 --- f_F8.0um [b] b for blended
55- 57 F3.1 uJy e_F8.0um ? rms uncertainty on F8.0um
59 A1 --- l_F24um Limit flag on F24um
60- 64 F5.1 uJy F24um ? Flux at 24um
65 A1 --- f_F24um [b] b for blended
66- 69 F4.1 uJy e_F24um ? rms uncertainty on F24um
70 A1 --- n_F24um [*] Note on ACO 1835 319 (1)
72- 79 E8.3 --- FXG1.0 (0.5-7.0keV) 3σ level X-ray flux limit
for photon spectral index Gamma=1.0
81- 88 E8.3 --- FXG2.0 (0.5-7.0keV) 3σ level X-ray flux limit
for photon spectral index Gamma=2.0
90- 97 E8.3 --- FXG1.4 (2.0-10.0keV) 3σ level X-ray flux limit
for photon spectral index Gamma=1.4
99-102 F4.2 --- mu0.5 Magnitication factor for zsource=0.5
104-107 F4.2 --- mu1.0 Magnitication factor for zsource=1.0
109-112 F4.2 --- mu1.5 Magnitication factor for zsource=1.5
114-117 F4.2 --- mu2.0 Magnitication factor for zsource=2.0
119-122 F4.2 --- mu3.0 Magnitication factor for zsource=3.0
124-127 F4.2 --- mu7.0 Magnitication factor for zsource=7.0
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Note (1): SED fitting are not able to explain the 24µ flux. ACO 1835 319
appears resolved into two sources. It remains to be seen, whether or
not we are looking at physically distinct sources, or objects which
are gravitationally bound.
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History:
From electronic version of the journal
References:
Schaerer et al., Paper I 2007A&A...469...47S 2007A&A...469...47S
(End) Patricia Vannier [CDS] 04-Feb-2008