J/ApJ/713/330 Spitzer observations of major-merger galaxies (Xu+, 2010)
Local benchmarks for the evolution of major-merger galaxies--
Spitzer observations of a K-band selected sample.
Xu C.K., Domingue D., Cheng Y.-W., Lu N., Huang J., Gao Y.,
Mazzarella J.M., Cutri R., Sun W.-H., Surace J.
<Astrophys. J., 713, 330-355 (2010)>
=2010ApJ...713..330X 2010ApJ...713..330X
ADC_Keywords: Galaxies, IR ; Photometry, infrared ; Redshifts ; Morphology ;
Active gal. nuclei
Keywords: galaxies: evolution - galaxies: general - galaxies: interactions -
galaxies: starburst
Abstract:
We present Spitzer observations for a sample of close major-merger
galaxy pairs (KPAIR sample) selected from cross-matches between the
2MASS Extended Source Catalog and Sloan Digital Sky Survey Data
Release 3. The goals are to study the star formation activity in these
galaxies and to set a local bench mark for the cosmic evolution of
close major mergers. The Spitzer KPAIR sample (27 pairs, 54 galaxies)
includes all spectroscopically confirmed spiral-spiral (S+S) and
spiral-elliptical (S+E) pairs in a parent sample that is complete for
primaries brighter than K=12.5 mag, projected separations of
5h-1kpc≤s≤20h-1kpc, and mass ratios ≤2.5. The Spitzer data,
consisting of images in seven bands (3.6, 4.5, 5.8, 8, 24, 70, 160um),
show very diversified IR emission properties.
Description:
IR imaging observations of all pairs but J1315+6207 in Table 1 were
carried out in 2005 and 2006 under the Spitzer Cycle 2 GO Program
"Local Benchmarks for the Evolution of Interacting Galaxies" (PID no.
20187). These include images in the four bands (3.6, 4.5, 5.8, and
8.0um) of the Infrared Array Camera (IRAC) and in three bands (24, 70,
and 160um) of the Multiband Imaging Photometer for Spitzer (MIPS).
KPAIR J1315+6207 (UGC08335a/b) is included in the Spitzer GO-1 survey
of LIRGs (J. M. Mazzarella et al. 2010, in preparation).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 83 54 KPAIR galaxy sample
table2.dat 91 29 The Spitzer observations of the 27 pairs
table3.dat 137 162 IR emission of paired galaxies
table4.dat 144 39 Galaxies in the control sample and their KPAIR
matches (non-AGN spirals)
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See also:
II/306 : The SDSS Photometric Catalog, Release 8 (Adelman-McCarthy+, 2011)
II/290 : SWIRE Photometric Redshift Catalogue (Rowan-Robinson+, 2008)
VII/233 : The 2MASS Extended sources (IPAC/UMass, 2003-2006)
J/ApJ/709/884 : Role of starburst-AGN composites in LIRG mergers (Yuan+, 2010)
J/AJ/132/2243 : Infrared properties of close pairs of galaxies (Geller+, 2006)
J/AJ/129/682 : Structural properties of S+S galaxies (Hernandez-Toledo+, 2005)
J/ApJ/560/566 : K-band galaxy luminosity function from 2MASS (Kochanek+, 2001)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- KPAIR Pair identification (JHHMM+DDMM)
12- 28 A17 --- 2MASX Galaxy identification (JHHMMSSss+DDMMSSs)
30- 31 I2 h RAh Hour of right ascension (J2000)
33- 34 I2 min RAm Minute of right ascension (J2000)
36- 39 F4.1 s RAs Second of right ascension (J2000)
41 A1 --- DE- Sign of declination (J2000)
42- 43 I2 deg DEd Degree of declination (J2000)
45- 46 I2 arcmin DEm Arcminute of declination (J2000)
48- 49 I2 arcsec DEs Arcsecond of declination (J2000)
51- 55 I5 km/s Vz SDSS-DR3 recession velocity
57- 61 F5.2 mag Ksmag 2MASX Ks-band (K20) magnitude
63- 67 F5.2 [Msun] logM Logarithm of the stellar mass of the galaxy
69 A1 --- Type [SE] Spiral (S) or Elliptical (E) (1)
71 A1 --- n_Type [12R]? AGN-type activity (2)
73- 77 F5.2 Jy F60 ? IRAS 60um flux density of the total pair
79- 83 F5.2 [Lsun] logL60 ? Log of the 60um luminosity (νLν) of
the total pair
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Note (1): Galaxies are classified as either "S" or "E" using the following
scheme: first, classical "eyeball" classifications were carried out.
Independently, two of us (C.K.X. and D.D.) inspected the SDSS optical
image of every galaxy in the sample and assigned a type to it
according to its morphology. In addition, we also run an automatic
classification script. It classifies a galaxy as "E" if u-r>2.22 and
R50/R90<0.35, where R50 and R90 are the radii containing 50%
and 90% of the Petrosian flux (Park & Choi 2005ApJ...635L..29P 2005ApJ...635L..29P).
Otherwise, the galaxy is classified as "S" type. The final
classification is the median of the two eyeball results and the result
of the automatic method.
Note (2): Galaxies containing known active galactic nuclei (AGNs; via NED)
are flagged with 1, 2, or R to indicate type 1, type 2, or radio AGNs.
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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- 10 A10 --- KPAIR Pair identification
11 A1 --- m_KPAIR [AB]? Multiple observation flag
13- 14 I2 h RAh Hour of right ascension (J2000)
16- 17 I2 min RAm Minute of right ascension (J2000)
19- 22 F4.1 s RAs Second of right ascension (J2000)
24 A1 --- DE- Sign of declination (J2000)
25- 26 I2 deg DEd Degree of declination (J2000)
28- 29 I2 arcmin DEm Arcminute of declination (J2000)
31- 32 I2 arcsec DEs Arcsecond of declination (J2000)
34- 41 A8 --- AOR IRAC AOR key
43- 50 A8 "YY/MM/DD" Date IRAC observation date
52- 59 A8 --- AORM MIPS AOR key
61- 68 A8 "YY/MM/DD" DateM MIPS observation date
70- 74 F5.1 s IRAC IRAC on-source time
76- 80 F5.1 s 24um MIPS 24um on-source time
82- 86 F5.1 s 70um MIPS 70um on-source time
88- 91 F4.1 s 160um MIPS 160um on-source time
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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- 17 A17 --- 2MASX Galaxy identification (JHHMMSSss+DDMMSSs)
19- 23 A5 kpc Ap Diameter of IRAC Aperture (4kpc, 10kpc or
Total)
25- 30 F6.2 mJy F3.6 Spitzer/IRAC 3.6um flux density
32- 36 F5.2 mJy e_F3.6 F3.6 uncertainty
38- 42 F5.2 mJy F4.5 Spitzer/IRAC 4.5um flux density
44- 47 F4.2 mJy e_F4.5 F4.5 uncertainty
49- 53 F5.2 mJy F5.8 Spitzer/IRAC 5.8um flux density
55- 59 F5.2 mJy e_F5.8 F5.8 uncertainty
61- 66 F6.2 mJy F8.0 Spitzer/IRAC 8.0um flux density
68- 72 F5.2 mJy e_F8.0 F8.0 uncertainty
74 A1 --- l_F24 Limit flag on F24
75- 80 F6.2 mJy F24 ? Spitzer/MIPS 24um flux density
82- 86 F5.2 mJy e_F24 ? F24 uncertainty
89 A1 --- l_F70 Limit flag on F70
90- 96 F7.2 mJy F70 ? Spitzer/MIPS 70um flux density
98-103 F6.2 mJy e_F70 ? F70 uncertainty
105 A1 --- l_F160 Limit flag on F160
106-112 F7.2 mJy F160 ? Spitzer/MIPS 160um flux density
114-119 F6.2 mJy e_F160 ? F160 uncertainty
121-123 A3 --- Flag Photometry flag (1)
125 A1 --- l_LTIR Limit flag on LTIR
126-130 F5.2 [Lsun] LTIR ? Total IR luminosity log(LTIR) (2)
132 A1 --- l_LIR Limit flag on LIR
133-137 F5.2 [Lsun] LIR ? IR luminosity log(LIR) (3)
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Note (1): Photometry methods for measurements of MIPS flux densities. "A"
stands for aperture photometry, "W" for weak source, and "P" for PRF
(Point Response Function) fitting. The three letters correspond to the
24, 70, and 160um bands, respectively. For example, "AAP" means that
flux densities in both the 24 and 70um bands were measured by aperture
photometry while the 160um flux density was measured by PRF fitting.
Note (2): 3-1000um IR luminosity, calculated from L24um, L70um, and
L160um using the formula of Dale & Helou (2002ApJ...576..159D 2002ApJ...576..159D).
Note (3): Second estimate of 3-1000um IR luminosity, calculated from L24um
and L8um. LIR is an unbiased estimator of LTIR
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Byte-by-byte Description of file: table4.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Gal Galaxy identification in the control sample
12- 13 I2 h RAh Hour of right ascension (J2000)
15- 16 I2 min RAm Minute of right ascension (J2000)
18- 21 F4.1 s RAs Second of right ascension (J2000)
23 A1 --- DE- Sign of declination (J2000)
24- 25 I2 deg DEd Degree of declination (J2000)
27- 28 I2 arcmin DEm Arcminute of declination (J2000)
30- 31 I2 arcsec DEs Arcsecond of declination (J2000)
33- 38 F6.4 --- z SDSS redshift
40- 44 F5.2 mag Ksmag 2MASX Ks-band (K20) magnitude
46 A1 --- l_F8.0 Limit flag on F8.0
47- 53 F7.2 mJy F8.0 Spitzer/IRAC 8.0um flux density from SWIRE-DR2
55- 60 F6.2 mJy e_F8.0 ? F8.0 uncertainty
62 A1 --- l_F24 Limit flag on F24
63- 69 F7.2 mJy F24 Spitzer/MIPS 24um flux density from SWIRE-DR2
71- 75 F5.2 mJy e_F24 ? F24 uncertainty
77- 81 F5.2 [Msun] logM Logarithm of the mass of the KPAIR galaxy
83 A1 --- l_logSFR Limit flag on logSFR
84- 89 F6.2 [yr-1] logSFR Specific star formation rate (log(SFR/M))
91-107 A17 --- 2MASX Matched KPAIR galaxy identification
(JHHMMSSss+DDMMSSs)
109-114 F6.4 --- z2 Redshift of the KPAIR galaxy
116-120 F5.2 [Msun] logM2 Log of the mass of the KPAIR galaxy
122 A1 --- l_logSFR2 Limit flag on logSFRK
123-128 F6.2 [yr-1] logSFR2 Specific SFR of the KPAIR galaxy (log scale)
130 A1 --- l_e Limit flag on e
131-135 F5.2 --- e SFR enhancement of the KPAIR galaxy (1)
137-139 A3 --- CAT Category of the KPAIR galaxy (2)
141-144 F4.2 --- SEP Scale free separation parameter (3)
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Note (1): SFR enhancement: ε=log((SFR/M)KPAIR-S)-log((SFR/M)control)
Note (2): Category of the KPAIR galaxy. For example, "SE1" indicates that
the galaxy is the primary of an S+E pair, and "SS2" denotes a
secondary in an S+S pair.
Note (3): Scale free separation parameter: SEP=s/(r1+r2), where s is
the pair separation, r1 the K-band Kron radius of the primary, and
r2 the K band Kron radius of the secondary.
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History:
From electronic version of the journal
(End) Emmanuelle Perret [CDS] 12-Apr-2012