J/ApJS/176/39 IR survey of brightest cluster galaxies I. (Quillen+, 2008)
An infrared survey of brightest cluster galaxies. I.
Quillen A.C., Zufelt N., Park J., O'Dea C.P., Baum S.A., Privon G.,
Noel-Storr J., Edge A., Russell H., Fabian A., Donahue M., Bregman J.N.,
McNamara B.R., Sarazin C.L.
<Astrophys. J. Suppl. Ser., 176, 39-58 (2008)>
=2008ApJS..176...39Q 2008ApJS..176...39Q
ADC_Keywords: Galaxies, IR ; Clusters, galaxy ; Photometry, infrared ; Surveys
Keywords: cooling flows - galaxies: active - galaxies: clusters: general
galaxies: elliptical and lenticular, cD - infrared: galaxies
stars: formation
Abstract:
We report on an imaging survey with the Spitzer Space Telescope of 62
brightest cluster galaxies (BCGs) with optical line emission. These
galaxies are located in the cores of X-ray luminous clusters selected
from the ROSAT All-Sky Survey. We find that about half of these
sources have a sign of excess infrared emission; 22 objects out of 62
are detected at 70um, 18 have 8/5.8um flux ratios above 1.0 and 28
have 24/8um flux ratios above 1.0. Altogether 35 of 62 objects in our
survey exhibit at least one of these signs of infrared excess. Four
galaxies with infrared excesses have a 4.5/3.6um flux ratio indicating
the presence of hot dust, and/or an unresolved nucleus at 8um. Three
of these have high measured [OIII](5007Å)/Hβ flux ratios
suggesting that these four, Abell 1068, Abell 2146, Zwicky 2089, and
R0821+07, host dusty active galactic nuclei (AGNs). Nine objects
(including the four hosting dusty AGNs) have infrared luminosities
greater than 1011L☉ and so can be classified as luminous
infrared galaxies (LIRGs). Excluding the four systems hosting dusty
AGNs, the excess mid-infrared emission in the remaining brightest
cluster galaxies is likely related to star formation.
Description:
The 3.6, 4.5, 5.8, and 8.0um broadband images were obtained during
cycle 3 (2007-2008) using the Infrared Array Camera (IRAC; Fazio et
al., 2004ApJS..154...10F 2004ApJS..154...10F) onboard Spitzer. The 24.4 and 70um images
were obtained using the Multiple Imaging Photometer for Spitzer
(MIPS; Rieke et al., 2004ApJS..154...25R 2004ApJS..154...25R).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 86 63 The brightest cluster galaxy sample and
comparison luminosities
table2.dat 53 63 Infrared photometry
table3.dat 25 63 Estimated infrared luminosities of BCGs
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See also:
J/A+AS/109/147 : ROSAT AGN content (Brinkmann+, 1995)
J/MNRAS/301/881 : The ROSAT brightest cluster sample - I. (Ebeling+, 1998)
J/MNRAS/306/857 : ROSAT Brightest Cluster Sample. III. (Crawford+, 1999)
J/ApJ/519/533 : ROSAT observations of ACO clusters (David+, 1999)
J/MNRAS/318/333 : Extended ROSAT Bright Cluster Sample (Ebeling+ 2000)
J/A+A/425/367 : REFLEX Galaxy Cluster Survey catalogue (Boehringer+, 2004)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Cluster name
17- 19 A3 --- n_Name [a-g, ] Notes on cluster (G1)
21- 22 I2 h RAh BCG Hour of right ascension (J2000) (2)
24- 25 I2 min RAm BCG Minute of right ascension (J2000) (2)
27- 31 F5.2 s RAs BCG Second of right ascension (J2000) (2)
33 A1 --- DE- BCG Declination sign (J2000) (2)
34- 35 I2 deg DEd BCG Degree of declination (J2000) (2)
37- 38 I2 arcmin DEm BCG Arcminute of declination (J2000) (2)
40- 43 F4.1 arcsec DEs BCG Arcsecond of declination (J2000) (2)
45- 50 F6.4 --- z Redshift
52- 56 F5.2 10+37W LX X-ray luminosity based on 0.1-2.4keV ROSAT
fluxes (in 1044erg/s) (3)
57 A1 --- f_LX [a] X-ray contamination (4)
59 I1 --- r_LX Luminosity measurement reference (5)
61- 66 F6.2 10+33W LHa ?=- Hα luminosity (in 1040erg/s)
68- 70 F3.1 --- O3/Hb ?=- [OIII](5007)/Hβ flux ratio
72- 73 I2 --- r_O3/Hb ? Optical line flux and ratio measurement
reference (5)
75 A1 --- l_L1.4GHz Limit flag on L1.4GHz (3σ upper limit)
76- 82 F7.3 10+24W/Hz L1.4GHz ?=- Integrated luminosities at 1.4GHz (6)
84- 85 I2 --- r_L1.4GHz ?=- Radio flux survey reference (5)
86 A1 --- Note [*] Duplicate line for RXC J0751.3+5012
(pair of galaxies)
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Note (2): Most of these positions are those listed by Crawford et al.
(1999, Cat. J/MNRAS/306/857)
Note (3): Excepting for Abell 11, which is based on 0.5-2keV. These have
been corrected to be consistent with a Hubble constant H0=70Mpc/km/s.
Note (4): The ROSAT flux is contaminated by an AGN so the cluster X-ray
luminosity is less than the number given here.
Note (5): References as follows:
1 = David et al., 1999ApJ...519..533D 1999ApJ...519..533D, (Cat. J/ApJ/519/533);
2 = Bohringer et al., 2004A&A...425..367B 2004A&A...425..367B, (Cat. J/A+A/425/367);
3 = Ebeling et al., 1998MNRAS.301..881E 1998MNRAS.301..881E, (Cat. J/MNRAS/301/881);
4 = Ebeling et al., 2000MNRAS.318..333E 2000MNRAS.318..333E, (Cat. J/MNRAS/318/333);
5 = Brinkmann et al., 1995A&AS..109..147B 1995A&AS..109..147B, (Cat. J/A+AS/109/147);
6 = Edge et al., 1990MNRAS.245..559E 1990MNRAS.245..559E;
7 = SDSS Spectral line measurements (Cat. II/294);
8 = Tables 5 and 6 by Crawford et al., 1999MNRAS.306..857C 1999MNRAS.306..857C,
(Cat. J/MNRAS/306/857);
9 = Based on Paα fluxes measured by Edge et al., 2002MNRAS.337...49E 2002MNRAS.337...49E;
10 = Table 1 by Jaffe et al., 2005MNRAS.360..748J 2005MNRAS.360..748J, and an intrinsic
Hα/Paα ratio of 8.46 for case B recombination at a temperature
of 104K and a density of 100cm^-3-;
11 = NVSS survey (Condon et al., 1998AJ....115.1693C 1998AJ....115.1693C, Cat. VIII/65);
12 = FIRST survey (Becker et al., 1995ApJ...450..559B 1995ApJ...450..559B; White et al.,
1997ApJ...475..479W 1997ApJ...475..479W, Cat. VIII/48 superseded by Cat. VIII/51).
Note (6): The objects lacking luminosities were not at positions covered by
either NVSS or FIRST surveys.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- Name Cluster designation
18 A1 --- n_Name [hij] Individual notes (G1)
20- 24 F5.2 mJy F3.6um IRAC 3.6um aperture photometry (2)
26- 30 F5.2 mJy F4.5um IRAC 4.5um aperture photometry (2)
32- 35 F4.2 mJy F5.8um IRAC 5.8um aperture photometry (2)
37- 41 F5.2 mJy F8um IRAC 8um aperture photometry (2)
43 A1 --- l_F24um Limit flag on 24um
44- 48 F5.2 mJy F24um IRAC 24um aperture photometry (2)
50 A1 --- l_F70um Limit flag on 70um
51- 53 I3 mJy F70um IRAC 70um aperture photometry
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Note (2): Aperture photometry at 3.6, 4.5, 5.8, 8, and 24.4um were measured
from the band 1-4 IRAC images and band 1 MIPS images. See text for
aperture corrections details.
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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- 16 A16 --- Name Cluster designation
17 A1 --- n_Name [*] Luminous IR galaxy (G1)
19 A1 --- l_LIR Limit flag on LIR
20- 24 F5.2 10+37W LIR Estimated infrared luminosity of BCG (2)
25 A1 --- Note [*] Duplicate line for RXC J0751.3+5012
(pair of galaxies)
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Note (2): Infrared luminosities are estimated from the flux at 15um
for BCGs that are either detected at 70um, have color ratio
F8um/F5.8um>1.0 or F24um/F8um>1.0. See section 3.3. The top section
contains four BCGs that are suspected to harbor dusty Type II AGNs.
Z2089, A2146 and A1068 exhibit a red F4.5um/F3.6um color and all four
have high [OIII](5007)/Hβ flux ratios. The second set is the
remaining 10 BCGs with F8um/F5.8um>1.3. The third section is the set
of six clusters with 1.0<F8um/F5.8um<1.3. The fourth set is the
remaining BCGs with IR excesses. Specifically, they have ratios
F8um/F5.8um>1.0, F24um/F8um>1.0, or a detected 70um flux. The last
section contains upper limits for the remaining objects.
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Global Notes:
Note (G1): Notes as follows:
a = sources were extended and so the NVSS flux was used, not the FIRST flux
b = sources had multiple components seen in the FIRST survey and these were
added to estimate the total
c = sources were extended in the NVSS images so fits images were used to
integrate the total
d = Objects with [NII] emission but no Hα reported by Crawford et al.
(1999, Cat. J/MNRAS/306/857).
e = Abell 4059 exhibits a similar spectrum with [NII] but no Hα as
seen from the 6dFGS archive (Jones et al., 2004MNRAS.355..747J 2004MNRAS.355..747J;
Jones et al., 2005, Cat. VII/249).
f = A3112 exhibits [OII] emission (Katgert et al., 1998,
Cat. J/A+AS/129/399), but we have failed to find a report of its
Hα emission.
g = Through an oversight A2622 was included in the sample, as it lacks
emission lines (Owen et al., 1995, Cat. J/AJ/109/14).
h = RXC J0751.3+5012 contains a pair of bright elliptical galaxies,
hence, two measurements are given, one for each galaxy.
i = Abell 2627 is a galaxy pair; photometry is only given for the
northern galaxy.
j = RXC J0338.6+0958 has a nearby bright star which is adding to
the uncertainty of the photometry.
* = BCGs marked with an asterisk have LIR>1011L☉ (4x1037W)
and can be classified as LIRGs (luminous infrared galaxies)
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 29-Jul-2009