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. =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](5007{AA})/H{beta} 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 10^11^L_{sun}_ 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) onboard Spitzer. The 24.4 and 70um images were obtained using the Multiple Imaging Photometer for Spitzer (MIPS; Rieke et al., 2004ApJS..154...25R). File Summary: -------------------------------------------------------------------------------- FileName Lrecl Records Explanations -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 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 10^44^erg/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 ?=- H{alpha} luminosity (in 10^40^erg/s) 68- 70 F3.1 --- O3/Hb ?=- [OIII](5007)/H{beta} 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 (3{sigma} 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) -------------------------------------------------------------------------------- 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 H_0_=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, (Cat. J/ApJ/519/533); 2 = Bohringer et al., 2004A&A...425..367B, (Cat. J/A+A/425/367); 3 = Ebeling et al., 1998MNRAS.301..881E, (Cat. J/MNRAS/301/881); 4 = Ebeling et al., 2000MNRAS.318..333E, (Cat. J/MNRAS/318/333); 5 = Brinkmann et al., 1995A&AS..109..147B, (Cat. J/A+AS/109/147); 6 = Edge et al., 1990MNRAS.245..559E; 7 = SDSS Spectral line measurements (Cat. II/294); 8 = Tables 5 and 6 by Crawford et al., 1999MNRAS.306..857C, (Cat. J/MNRAS/306/857); 9 = Based on Pa{alpha} fluxes measured by Edge et al., 2002MNRAS.337...49E; 10 = Table 1 by Jaffe et al., 2005MNRAS.360..748J, and an intrinsic H{alpha}/Pa{alpha} ratio of 8.46 for case B recombination at a temperature of 10^4^K and a density of 100cm^-3-; 11 = NVSS survey (Condon et al., 1998AJ....115.1693C, Cat. VIII/65); 12 = FIRST survey (Becker et al., 1995ApJ...450..559B; White et al., 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. -------------------------------------------------------------------------------- Byte-by-byte Description of file: table2.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 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 -------------------------------------------------------------------------------- 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. -------------------------------------------------------------------------------- Byte-by-byte Description of file: table3.dat -------------------------------------------------------------------------------- Bytes Format Units Label Explanations -------------------------------------------------------------------------------- 1- 16 A16 --- Name Cluster designation 17 A1 --- n_Name [*] Luminous IR galaxy (G1) 19 A1 --- l_LIR Limit flag on L_IR_ 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) -------------------------------------------------------------------------------- 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)/H{beta} 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 1.01.0, F24um/F8um>1.0, or a detected 70um flux. The last section contains upper limits for the remaining objects. -------------------------------------------------------------------------------- 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 H{alpha} reported by Crawford et al. (1999, Cat. J/MNRAS/306/857). e = Abell 4059 exhibits a similar spectrum with [NII] but no H{alpha} as seen from the 6dFGS archive (Jones et al., 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 H{alpha} 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 L_IR_>10^11^L_{sun}_ (4x10^37^W) and can be classified as LIRGs (luminous infrared galaxies) -------------------------------------------------------------------------------- History: From electronic version of the journal ================================================================================ (End) Emmanuelle Perret [CDS] 29-Jul-2009