J/MNRAS/480/3562 AGN luminosity fraction in merging galaxies (Dietrich+, 2018)
The AGN luminosity fraction in merging galaxies.
Dietrich J., Weiner A.S., Ashby M.L.N., Hayward C.C.,
Martinez-Galarza J.R., Ramos Padilla A.F., Rosenthal L., Smith H.A.,
Willner S.P., Zezas A.
<Mon. Not. R. Astron. Soc., 480, 3562-3583 (2018)>
=2018MNRAS.480.3562D 2018MNRAS.480.3562D (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Galaxies, IR ; Galactic center ;
Galaxies, photometry
Keywords: galaxies: interactions - galaxies: photometry -
galaxies: star formation - infrared: galaxies -
galaxies: active - galaxies: nuclei
Abstract:
Galaxy mergers are key events in galaxy evolution, often causing
massive starbursts and fueling active galactic nuclei (AGNs). In these
highly dynamic systems, it is not yet precisely known how much
starbursts and AGNs, respectively, contribute to the total luminosity,
at what interaction stages they occur, and how long they persist. Here
we estimate the fraction of the bolometric infrared (IR) luminosity
that can be attributed to AGNs by measuring and modeling the full
ultraviolet to far-IR spectral energy distributions (SEDs) in up to 33
broad bands for 24 merging galaxies with the Code for Investigating
Galaxy Emission. In addition to a sample of 12 confirmed AGNs in
late-stage mergers, found in the Infrared Astronomical Satellite
Revised Faint Source Catalog, our sample includes a comparison sample
of 12 galaxy mergers from the Spitzer Interacting Galaxies Survey,
mostly early stage. We also perform SED modeling of merger simulations
to validate our methods, and we supplement the SEDs with mid-IR
spectra of diagnostic lines obtained with Spitzer's InfraRed
Spectrograph. The estimated AGN contributions to the IR luminosities
vary from system to system from 0 per cent up to ∼91 per cent but
are significantly greater in the later-stage, more luminous mergers,
consistent with what is known about galaxy evolution and AGN
triggering.
Description:
We chose the late-stage merger sample to represent strongly
interacting, IR-luminous systems. Candidate systems were identified by
the Infrared Astronomical Satellite (IRAS; Neugebauer et al.
1984ApJ...278L...1N 1984ApJ...278L...1N) Revised Faint Source Catalogue (FSC; Wang et al.
2014MNRAS.442.2739W 2014MNRAS.442.2739W) and the IRAS Revised Bright Galaxy Sample
(Sanders et al. 2003AJ....126.1607S 2003AJ....126.1607S, Cat. J/AJ/126/1607). We selected
interacting systems by cross-referencing IRAS sources with Version 2
of the Galaxy Zoo public galaxy classification program (Willett et al.
2013MNRAS.435.2835W 2013MNRAS.435.2835W, Cat. J/MNRAS/435/2835) to yield 453 systems. We
classified all these systems by merger stage finding 38 with
morphological evidence for strong interaction such as long tidal tails
or heavily disturbed morphology. Of these 38 galaxies, only 12 had
available photometry from all of Spitzer/IRAC, Spitzer/MIPS 24µm,
and Herschel/SPIRE at 250, 350, and 500µm, respectively. These 12
constitute the late-stage merger sample. For a control set to compare
with the late-stage mergers, a 'Reference Sample' was drawn from the
SIGS galaxy sample (Brassington et al. 2015ApJS..218....6B 2015ApJS..218....6B, Cat.
J/ApJS/218/6). From the SIGS sample, we selected 12 galaxies with
UV-submm photometry comparable to what was available for the
Late-Stage Merger Sample.
Tables B1 to B7 show the photometry and PACS spectrophotometric data
for both samples. Table C1 shows the AGN observables linear fit
analysis.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tableb1.dat 116 24 GALEX and Swift UV photometry
tableb2.dat 121 24 SDSS photometry
tableb3.dat 142 24 2MASS and IRAS photometry
tableb4.dat 93 12 WISE photometry for the late-stage merger sample
tableb5.dat 137 24 Spitzer/IRAC and MIPS photometry
tableb6.dat 118 24 Herschel/PACS and SPIRE photometry
tableb7.dat 70 9 The PACS spectrophotometric (SP) data points,
with wavelength, number of observations,
and average flux
tablec1.dat 56 57 The linear regression test results of fAGN
versus colours showing the strongest
correlations (Pearson r>0.8) and their
significance across both subsamples
(requiring at least 3σ significance)
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Byte-by-byte Description of file: tableb1.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Sample Sample name
26- 40 A15 --- Name Galaxy name
42- 48 F7.3 mJy FUV ? Far ultraviolet GALEX flux density
50- 55 F6.3 mJy e_FUV ? Error on FUV
57- 63 F7.3 mJy NUV ? Near ultraviolet GALEX flux density
65- 70 F6.3 mJy e_NUV ? Error on NUV
72- 77 F6.3 mJy uvw2 ? Swift/UVOT UVW2-band flux density
79- 84 F6.3 mJy e_uvw2 ? Error on uvw2
86- 93 F8.3 mJy uvm2 ? Swift/UVOT UVM2-band flux density
95-101 F7.3 mJy e_uvm2 ? Error on uvm2
103-109 F7.2 mJy uvw1 ? Swift/UVOT UVW1-band flux density
111-116 F6.2 mJy e_uvw1 ? Error on uvw1
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Byte-by-byte Description of file: tableb2.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Sample Sample Name
26- 40 A15 --- Name Galaxy name
42- 49 F8.3 mJy Fu SDSS flux density in the u-band
51- 56 F6.3 mJy e_Fu Error on Fu
58- 65 F8.3 mJy Fg SDSS flux density in the g-band
67- 72 F6.3 mJy e_Fg Error on Fg
74- 80 F7.2 mJy Fr SDSS flux density in the r-band
82- 88 F7.3 mJy e_Fr Error on Fr
90- 97 F8.2 mJy Fi ? SDSS flux density in the i-band
99-105 F7.3 mJy e_Fi ? Error on Fi
107-114 F8.2 mJy Fz ? SDSS flux density in the z-band
116-121 F6.2 mJy e_Fz ? Error on Fz
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Byte-by-byte Description of file: tableb3.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Sample Sample name
26- 40 A15 --- Name Galaxy name
42- 49 F8.2 mJy FJ 2MASS J-band flux density
51- 56 F6.2 mJy e_FJ Error on FJ
58- 65 F8.2 mJy FH 2MASS H-band flux density
67- 72 F6.2 mJy e_FH Error on FH
74- 81 F8.2 mJy FKs 2MASS Ks-band flux density
83- 88 F6.2 mJy e_FKs Error on FKs
90- 95 F6.1 mJy S12 ? IRAS 12µm flux density
97-101 F5.1 mJy e_S12 ? Error on S12
103-109 F7.1 mJy S25 ? IRAS 25µm flux density
111-116 F6.1 mJy e_S25 ? Error on S25
118-123 I6 mJy S60 IRAS 60µm flux density
125-129 I5 mJy e_S60 Error on S60
131-136 I6 mJy S100 ?=- IRAS 100µm flux density
138-142 I5 mJy e_S100 ?=- Error on S100
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Byte-by-byte Description of file: tableb4.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Sample Sample name
26- 40 A15 --- Name Galaxy name
42- 47 F6.2 mJy FW1 ? WISE 3.4µm flux density
49- 53 F5.2 mJy e_FW1 ? Error on FW1
55- 60 F6.2 mJy FW2 ? WISE 4.6µm flux density
62- 66 F5.2 mJy e_FW2 ? Error on FW2
68- 73 F6.1 mJy FW3 ? WISE 12µm flux density
75- 80 F6.2 mJy e_FW3 ? Error on FW3
82- 87 F6.1 mJy FW4 ? WISE 22µm flux density
89- 93 F5.1 mJy e_FW4 ? Error on FW4
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Byte-by-byte Description of file: tableb5.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Sample Sample name
26- 40 A15 --- Name Galaxy name
42- 49 F8.2 mJy IRAC1 IRAC 3.6µm flux density
51- 56 F6.2 mJy e_IRAC1 Error on IRAC1
58- 64 F7.2 mJy IRAC2 IRAC 4.5µm flux density
66- 71 F6.2 mJy e_IRAC2 Error on IRAC2
73- 78 F6.1 mJy IRAC3 IRAC 5.8µm flux density
80- 85 F6.2 mJy e_IRAC3 Error on IRAC3
87- 92 F6.1 mJy IRAC4 ? IRAC 8.0µm flux density
94- 98 F5.1 mJy e_IRAC4 ? Error on IRAC4
100-106 F7.1 mJy MIPS1 ? MPSI 24µm flux density
108-112 F5.1 mJy e_MIPS1 ? Error on MIPS1
114-119 I6 mJy MIPS2 ?=- MPSI 70µm flux density
121-124 I4 mJy e_MIPS2 ?=- Error on MIPS2
126-131 I6 mJy MIPS3 ?=- MPSI 160µm flux density
133-137 I5 mJy e_MIPS3 ?=- Error on MIPS3
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Byte-by-byte Description of file: tableb6.dat
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Bytes Format Units Label Explanations
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1- 24 A24 --- Sample Sample name
26- 40 A15 --- Name Galaxy name
42- 47 I6 mJy PACS1 ?=- PACS 75µm flux density
49- 53 I5 mJy e_PACS1 ?=- Error on PACS1
55- 60 I6 mJy PACS2 ?=- PACS 110µm flux density
62- 66 I5 mJy e_PACS2 ?=- Error on PACS2
68- 73 I6 mJy PACS3 ?=- PACS 170µm flux density
75- 79 I5 mJy e_PACS3 ?=- Error on PACS3
81- 86 I6 mJy SPIRE1 SPIRE 250µm flux density
88- 92 I5 mJy e_SPIRE1 Error on SPIRE1
94- 98 I5 mJy SPIRE2 SPIRE 350µm flux density
100-103 I4 mJy e_SPIRE2 Error on SPIRE2
105-111 F7.1 mJy SPIRE3 SPIRE 500µm flux density
113-118 F6.1 mJy e_SPIRE3 Error on SPIRE3
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Byte-by-byte Description of file: tableb7.dat
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Bytes Format Units Label Explanations
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1- 15 A15 --- Name Galaxy name
17- 18 I2 um wlBlue PACS Blue filter wavelenght
20- 22 I3 --- o_FBlue ?=- Number of observations at wlBlue (1)
24- 28 I5 mJy FBlue Flux density at wlBlue
30- 33 I4 mJy e_FBlue Error on FBlue
35- 36 I2 um wlGreen PACS Green filter wavelenght
38- 40 I3 --- o_FGreen ?=- Number of observations at wlGreen (1)
42- 46 I5 mJy FGreen Flux density at wlGreen
48- 51 I4 mJy e_FGreen Error on FGreen
53- 55 I3 um wlRed PACS Red filter wavelenght
57- 59 I3 --- o_FRed ?=- Number of observations at wlRed (1)
61- 65 I5 mJy FRed Flux density at wlRed
67- 70 I4 mJy e_FRed Error on FRed
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Note (1): - signifies unknown number of observations were used
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Byte-by-byte Description of file: tablec1.dat
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Bytes Format Units Label Explanations
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1- 28 A28 --- FluxRatio Flux ratios
30- 31 I2 --- N(S) Number of systems
33- 37 F5.2 --- Slope Slope of the linear regression test of fAGN
versus every flux ratio (1)
39- 42 F4.2 --- e_Slope Error on Slope
44- 48 F5.2 --- r Pearson correlation ratio
50- 56 E7.3 --- p p-value (requiring at least a significance
level of 3σ)
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Note (1): fAGN is defined as the AGN fraction to the IR luminosity
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History:
From electronic version of the journal
(End) Ana Fiallos [CDS] 23-May-2022