J/AJ/132/2243 Infrared properties of close pairs of galaxies (Geller+, 2006)
Infrared properties of close pairs of galaxies.
Geller M.J., Kenyon S.J., Barton E.J., Jarrett T.H., Kewley L.J.
<Astron. J., 132, 2243-2259 (2006)>
=2006AJ....132.2243G 2006AJ....132.2243G
ADC_Keywords: Galaxies, IR ; Photometry, infrared
Keywords: galaxies: interactions - galaxies: photometry - galaxies: starburst
Abstract:
We discuss spectroscopy and IR photometry for a complete sample of
∼800 galaxies in close pairs objectively selected from the second
Center for Astrophysics redshift survey. We use the Two Micron All Sky
Survey to compare near-IR color-color diagrams for our sample with the
Nearby Field Galaxy Sample and with a set of IRAS flux-limited pairs
from Surace and coworkers. We construct a basic statistical model to
explore the physical sources of the substantial differences among
these samples. The model explains the spread of near-IR colors and is
consistent with a picture in which central star formation is triggered
by the galaxy-galaxy interaction before a merger occurs. For 160
galaxies we report new, deep JHK photometry within our spectroscopic
aperture, and we use the combined spectroscopic and photometric data
to explore the physical conditions in the central bursts.
Description:
We downloaded JHKs from the 2MASS extended source catalog using the
Infrared Science Archive (IRSA) Web interface at IPAC.1 All 791
galaxies in the complete pairs sample are detected.
We acquired JHK images of 160 pair galaxies in the sample of Barton
Gillespie et al. (2003, Cat. J/ApJ/582/668) along with standard
stars. These pairs are a random selection of the Baront et al.
(2000ApJ...530..660B 2000ApJ...530..660B) pairs. We used several NIR cameras at the Fred
L. Whipple Observatory 1.2m and the Kitt Peak National Observatory
2.1m telescopes.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 60 791 2MASS Infrared Photometry
table2.dat 44 8 Journal of observations
table3.dat 50 160 BGK Infrared Photometry (Cat. J/ApJ/582/668)
table4.dat 57 368 IRAS mid-infrared photometry
table5.dat 53 4 BGK00 pairs ((2000ApJ...530..660B 2000ApJ...530..660B) brighter than
Surace flux limits
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See also:
J/ApJ/582/668 : Colours and Hα in galaxy pairs (Barton Gillespie+, 2003)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 16 A16 --- 2MASX The J2000 Designation (HHMMSSss+DDMMSSs)
18- 22 I5 km/s cz Heliocentric radial velocity
24- 28 F5.2 mag Jmag7 2MASS J band 7" aperture magnitude
30- 34 F5.2 mag Hmag7 2MASS H band 7" aperture magnitude
36- 40 F5.2 mag Kmag7 2MASS Ks band 7" aperture magnitude
42- 46 F5.2 mag Jmagiso 2MASS J band 20mag/arcsec2 isophotal
elliptical magnitude
48- 52 F5.2 mag Hmagiso 2MASS H band 20mag/arcsec2 isophotal
elliptical magnitude
54- 58 F5.2 mag Kmagiso 2MASS Ks band 20mag/arcsec2 isophotal
elliptical magnitude
60 A1 --- f_2MASX [+*] Flag (1)
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Note (1): Flag as follows:
* = a previously unresolved object.
+ = undetected or confused with nearby stars or nearby non-pair
galaxies. Reanalyzed by T.H.J.
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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 "Y/M/D" Date UT Date of observation
11 A1 --- --- [-]
12- 21 A10 "Y/M/D" Date2 Second UT date of observation
23- 26 A4 --- Tel Telescope
28- 36 A9 --- IR IR Imager
38- 40 I3 arcsec Field1 Field of view
41 A1 --- --- [x]
42- 44 I3 arcsec Field2 Field of view
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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 --- 2MASX The J2000 Designation (HHMMSSss+DDMMSSs)
18- 21 F4.1 arcsec Length Slit length
23- 25 F3.1 arcsec Width Slit width
27- 30 F4.1 deg PA Position angle
32- 36 F5.2 mag Jmag The J band slit magnitude
38- 42 F5.2 mag Hmag The H band slit magnitude
44- 48 F5.2 mag Kmag The K band slit magnitude
50 A1 --- f_2MASX [*] Galaxies without optical spectrum (1)
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Note (1): These nine galaxies are without optical spectra so we adopted the
median slit length, 20", and the typical position angle of 90°.
The colors of these galaxies span the range of J-H and H-K colors of
other galaxies in the sample.
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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- 16 A16 --- 2MASX The J2000 Designation (HHMMSSss+DDMMSSs)
18- 27 A10 --- IRAS The IRAS Designation (1)
29 A1 --- l_S12um Limit flag on S12um (quality flag 1)
30- 33 F4.2 Jy S12um IRAS 12 micron flux density
34 A1 --- u_S12um [:] : for approximate flux (quality flag 2)
36 A1 --- l_S25um Limit flag on S25um (quality flag 1)
37- 40 F4.2 Jy S25um IRAS 25 micron flux density
41 A1 --- u_S25um [:] : for approximate flux (quality flag 2)
43 A1 --- l_S60um Limit flag on S60um (quality flag 1)
44- 48 F5.2 Jy S60um IRAS 60 micron flux density
49 A1 --- u_S60um [:] : for approximate flux (quality flag 2)
51 A1 --- l_S100um Limit flag on S100um (quality flag 1)
52- 56 F5.2 Jy S100um IRAS 100 micron flux density
57 A1 --- u_S100um [:] : for approximate flux (quality flag 2)
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Note (1): To preserve associations of IRAS detections with pair galaxies,
we list IRAS associations for each galaxy in the pair. This listing
duplicates flux measurements for pair galaxies where IRAS could not
spatially resolve the pair.
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Byte-by-byte Description of file: table5.dat
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Bytes Format Units Label Explanations
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1- 19 A19 --- Pair Pair designation (HHMMSS.ss+DDMMSS.ss)
21- 30 A10 --- IRAS IRAS name
32- 35 F4.2 Jy F12um Flux at 12um
36 A1 --- u_F12um Uncertainty flag on F12um
38- 41 F4.2 Jy F25um Flux at 25um
43- 47 F5.2 Jy F60um Flux at 60um
49- 53 F5.2 Jy F100um Flux at 100um
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History:
From electronic version of the journal
(End) Greg Schwarz [AAS], Patricia Vannier [CDS] 25-Jul-2008