J/ApJ/727/14 Merging galaxy cluster A2255 in mid-IR (Shim+, 2011)
Merging galaxy cluster A2255 in mid-infrared.
Shim H., Im M., Lee H.M., Lee M.G., Kim S.J., Hwang H.S., Hwang N., Ko J.,
Lee J.C., Lim S., Matsuhara H., Seo H., Wada T., Goto T.
<Astrophys. J., 727, 14 (2011)>
=2011ApJ...727...14S 2011ApJ...727...14S
ADC_Keywords: Clusters, galaxy ; Galaxies, IR ; Photometry, infrared ;
Photometry, SDSS ; Redshifts
Keywords: galaxies: clusters: individual (A2255) - galaxies: photometry -
infrared: galaxies
Abstract:
We present the mid-infrared (MIR) observation of a nearby galaxy
cluster, A2255, by the AKARI space telescope. Using AKARI's continuous
wavelength coverage between 3 and 24um and the wide field of view, we
investigate the properties of cluster member galaxies to see how the
infall of the galaxies, the cluster substructures, and the
cluster-cluster merger influence their evolution. We show that the
excess of MIR (∼11um) flux is a good indicator for discriminating
galaxies at different evolutionary stages and for dividing galaxies
into three classes accordingly: strong MIR-excess (N3-S11>0.2)
galaxies that include both unobscured and obscured star-forming
galaxies; weak MIR-excess (-2.0<N3-S11←1.2) galaxies that are
quiescent, old (>5Gyr) galaxies where the MIR emission arises mainly
from the circumstellar dust around AGB stars; and intermediate
MIR-excess (-1.2<N3-S11<0.2) galaxies in between the two classes that
are less than a few Gyr old past the prime star formation activity.
With the MIR-excess diagnostics, we investigate how local and
cluster-scale environments affect the individual galaxies. We derive
the total star formation rate (SFR) and the specific SFR of A2255
using the strong MIR-excess galaxies.
Description:
A2255 is one of the target galaxy clusters for the low-redshift
CLusters of galaxies EVoLution studies (CLEVL) program (Im et al.
2008ASPC..399..382I 2008ASPC..399..382I; Lee et al. 2009ASPC..418..241L 2009ASPC..418..241L) and is
observed by the AKARI InfraRed Camera (IRC) over eight fields (Figure
1), with each field covering an area of 10x10arcmin2.
A2255 was also observed by Spitzer MIPS 24um and 70um at 5σ flux
limits of 250uJy and 5mJy, respectively (PID 40562, PI: G. Rieke).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table2.dat 180 426 AKARI IRC 3-24µm, and Spitzer MIPS 24/70µm
photometry of Abell 2255 member galaxies
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See also:
II/306 : The SDSS Photometric Catalog, Release 8 (Adelman-McCarthy+, 2011)
II/297 : AKARI/IRC mid-IR all-sky Survey (ISAS/JAXA, 2010)
J/other/JApA/32.567 : Rotation measures in A2255 at 18, 21, 25, 85cm (Pizzo+
2011)
J/ApJS/149/53 : Multicolor photometry of A2255 galaxies (Yuan+, 2003)
J/AJ/124/2453 : Spectroscopy of active galaxies in nearby clusters (Miller+,
2002)
Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
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1- 6 A6 --- --- [A2255_]
7 A1 --- f_ID [P/S] P=photometric member or S=spectroscopic
member
8- 25 A18 --- ID Galaxy ID (HHMMSS.ss+DDMMSS.s; J2000)
27- 35 F9.5 deg RAdeg Right Ascension in decimal degrees (J2000)
37- 45 F9.5 deg DEdeg Declination in decimal degrees (J2000)
47- 54 F8.6 --- z Redshift (1)
56- 60 F5.2 mag umag ?=99.99 SDSS-DR2 u band AB magnitude (2)
62- 66 F5.2 mag gmag ?=99.99 SDSS-DR2 g band AB magnitude (2)
68- 72 F5.2 mag rmag ?=99.99 SDSS-DR2 r band AB magnitude (2)
74- 78 F5.2 mag imag ?=99.99 SDSS-DR2 i band AB magnitude (2)
80- 84 F5.2 mag zmag ?=99.99 SDSS-DR2 z band AB magnitude (2)
86- 90 F5.2 mag N3 ?=99.99 AKARI N3 band AB magnitude (3um) (2)
92- 96 F5.2 mag e_N3 ?=99.99 Error in N3 (2)
98-102 F5.2 mag N4 ?=99.99 AKARI N4 band AB magnitude (4um) (2)
104-108 F5.2 mag e_N4 ?=99.99 Error in N4 (2)
110-114 F5.2 mag S7 ?=99.99 AKARI S7 band AB magnitude (7um) (2)
116-120 F5.2 mag e_S7 ?=99.99 Error in S7 (2)
122-126 F5.2 mag S11 ?=99.99 AKARI S11 band AB magnitude (11um) (2)
128-132 F5.2 mag e_S11 ?=99.99 Error in S11 (2)
134-138 F5.2 mag L15 ?=99.99 AKARI L15 band AB magnitude (15um) (2)
140-144 F5.2 mag e_L15 ?=99.99 Error in L15 (2)
146-150 F5.2 mag L24 ?=99.99 AKARI L24 band AB magnitude (24um) (2)
152-156 F5.2 mag e_L24 ?=99.99 Error in L24 (2)
158-162 F5.2 mag [24] ?=99.99 Spitzer/MIPS 24 um band AB magnitude (2)
164-168 F5.2 mag e_[24] ?=99.99 Error in [24] (2)
170-174 F5.2 mag [70] ?=99.99 Spitzer/MIPS 70 um band AB magnitude (2)
176-180 F5.2 mag e_[70] ?=99.99 Error in [70] (2)
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Note (1): Redshifts of the spectroscopically selected members ("S") are
from SDSS DR2 (Abazajian et al. 2004AJ....128..502A 2004AJ....128..502A), while redshifts
of the photometrically selected members ("P") are from Yuan, Zhou, &
Jiang (2003, Cat. J/ApJS/149/53; <[YZJ2003] 4-NNN> or 2-NNN in Simbad).
Note (2): The magnitudes represent total magnitudes of the galaxies. The
value 99.00 indicates non-detection (below the detection limit- see
text for details), and 99.99 indicates that the source is either out
of the field of view in the observation, blended, etc.
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Emmanuelle Perret [CDS] 17-Aug-2012