J/A+A/570/A110 Mid-IR properties of OH maser galaxies (Zhang+, 2014)
The middle infrared properties of OH megamaser host galaxies.
Zhang J.S., Wang J.Z., Di G.X., Zhu Q.F., Guo Q., Wang J.
<Astron. Astrophys., 570, A110-110 (2014)>
=2014A&A...570A.110Z 2014A&A...570A.110Z
ADC_Keywords: Masers ; Active gal. nuclei ; Galaxies, IR ; Photometry, infrared
Keywords: masers - galaxies: active - galaxies: nuclei - infrared: galaxies
Abstract:
We compiled all 119 OH maser galaxies (110 out of them are megamasers,
i.e., LOH>10L☉) published so far and cross-identified these OH
masers with the Wide-Field Infrared Survey Explorer (WISE) catalog, to
investigate the middle infrared (MIR) properties of OH maser galaxies.
The WISE magnitude data at the 3.4, 4.6, 12 and 22µm (W1 to W4) are
collected for the OH maser sample and one control sample, which are
non-detection sources. The color-color diagrams show that both OH
megamaser (OHM) and non-OHM (ultra)luminous infrared galaxies
((U)LIRGs) are far away from the single blackbody model line and many
of them can follow the path described by the power-law model. The
active galaxy nuclei (AGN) fraction is about ∼40% for both OHM and
non-OHM (U)LIRGs, according to the AGN criteria W1-W2≥0.8. Among the
Arecibo survey sample, OHM sources tend to have a lower luminosity at
short MIR wavelengths (e.g., 3.4µm and 4.6µm) than that of
non-OHM sources, which should come from the low OHM fraction among the
survey sample with large 3.4µm and 4.6µm luminosity. The OHM
fraction tends to increase with cooler MIR colors (larger
F22µm/F3.4µm). These may be good for sample selection when
searching OH megamasers, such as excluding extreme luminous sources at
short MIR wavelengths, choosing sources with cooler MIR colors. In the
case of the power-law model, we derived the spectral indices for our
samples. For the Arecibo survey sample, OHM (U)LIRGs tend to have
larger spectral index α22-12 than non-OHM sources, which
agrees with previous results. One significant correlation exists
between the WISE infrared luminosity at 22µm and the color
[W1]-[W4] for the Arecibo OHM hosts. These clues should provide
suitable constraints on the sample selection for OH megamaser surveys
by future advanced telescopes (e.g., FAST). In addition, the
correlation of maser luminosity and the MIR luminosity of maser hosts
tends to be non-significant, which may indirectly support the pumping
of OHM emission that is dominated by the far infrared radiation,
instead of the MIR radiation.
Description:
All OH maser galaxies published so far were cross-correlated to the
All-Sky data release1 using the default search radius of 10". The
retrieved WISE sources were found for all maser sources except IRAS
11257+5850 and IRAS 20550+1655.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table4.dat 102 119 *WISE data of OH maser host galaxies
table5.dat 102 259 *WISE data of non-masing galaxies
table6.dat 108 107 Physical parameters of OH maser host galaxies
table7.dat 113 259 Physical parameters of non-masing galaxies
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Note on table4.dat: Sources with no WISE data represent nominally detected
galaxies, but no useful brightness estimate could be made.
Note on table5.dat: (U)LIRGs without OH detections in the Arecibo survey,
taken from Darling & Giovanelli (2000AJ....119.3003D 2000AJ....119.3003D, 2001AJ....121.1278D 2001AJ....121.1278D,
2002AJ....124..100D 2002AJ....124..100D, Cat. J/AJ/124/100).
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See also:
J/AJ/124/100 : OH megamasers at z>0.1. III (Darling+, 2002)
J/AJ/133/496 : OH megamasers infrared photometry (Chen+, 2007)
Byte-by-byte Description of file: table4.dat table5.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- IRAS IRAS name (HHMMm+DDMM, B1950) of OHM sources
11 A1 --- n_IRAS [*] * indicates kilomaser
12 A1 --- r_IRAS [abc] Reference on IRAS (1)
14- 15 I2 h RAh Right ascension (J2000) (2)
17- 18 I2 min RAm Right ascension (J2000)
20- 24 F5.2 s RAs Right ascension (J2000)
26 A1 --- DE- Declination sign (J2000) (2)
27- 28 I2 deg DEd Declination (J2000)
30- 31 I2 arcmin DEm Declination (J2000)
33- 36 F4.1 arcsec DEs Declination (J2000)
38- 42 F5.3 arcsec Dr ?=- Distance between positions of source
in 2MASS PSC and associated WISE source
46- 51 F6.3 mag W1 ?=- WISE 3.5um magnitude
53- 57 F5.3 mag e_W1 ?=- rms uncertainty on W1
59- 60 A2 --- l_W2 [>≤ ] Limit flag on W2
61- 66 F6.3 mag W2 ?=- WISE 4.6um magnitude
68- 72 F5.3 mag e_W2 ?=- rms uncertainty on W2
74- 75 A2 --- l_W3 [>≤ ] Limit flag on W3 (3)
76- 81 F6.3 mag W3 ?=- WISE 12um magnitude
83- 87 F5.3 mag e_W3 ?=- rms uncertainty on W3
89- 90 A2 --- l_W4 [>≤ ] Limit flag on W4 (4)
91- 96 F6.3 mag W4 ?=- WISE 22um magnitude
98-102 F5.3 mag e_W4 ?=- rms uncertainty on W4
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Note (1): References for all 119 published extragalactic OH maser galaxies:
a = from Willett (2012, IAU Symp., 287, 345)
b = from Fernandez et al. (2010AJ....139.2066F 2010AJ....139.2066F)
c = from Chen et al. (2007AJ....133..496C 2007AJ....133..496C, Cat. J/AJ/133/496)
Note (2): Equatorial coordinates in J2000 from 2MASS PSC reference frame.
Note (3): Three sources (IRAS 14586+1432, 17161+2006, and 21077+3358) with
e_W3 value of null show that their W3 profile-fit magnitude is a 95%
confidence upper limit or the source is not measurable.
Note (4): Four sources (IRAS 09513+1430, 14586+1432, 17161+2006, and 21077+3358)
with e_W4 value of null show that their W4 profile-fit magnitude is a 95%
confidence upper limit, or the source is not measurable.
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Byte-by-byte Description of file: table6.dat table7.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- IRAS IRAS name of OHM sources
12- 13 A2 --- l_W1 [>≤ ] Limit flag on W1
14- 19 F6.3 mag W1 ?=- WISE 3.5um magnitude
21- 22 A2 --- l_logLW1 [≤ ] Limit flag on W1
23- 28 F6.3 [Lsun] logLW1 ?=- WISE 3.5um corresponding luminosity (1)
29- 30 A2 --- l_W2 [>≤ ] Limit flag on W2
31- 36 F6.3 mag W2 ?=- WISE 4.6um magnitude
38- 39 A2 --- l_logLW2 [≤ ] Limit flag on W2
40- 44 F5.2 [Lsun] logLW2 ?=- WISE 4.6um corresponding luminosity (1)
46- 47 A2 --- l_W3 [>≤ ] Limit flag on W3
48- 53 F6.3 mag W3 ?=- WISE 12um magnitude
55- 56 A2 --- l_logLW3 [≤ ] Limit flag on W3
57- 61 F5.2 [Lsun] logLW3 ?=- WISE 12um corresponding luminosity (1)
63- 64 A2 --- l_W4 [>≤ ] Limit flag on W4
65- 70 F6.3 mag W4 ?=- WISE 22um magnitude
72- 73 A2 --- l_logLW4 [≤ ] Limit flag on W4
74- 78 F5.2 [Lsun] logLW4 ?=- WISE 22um corresponding luminosity (1)
80- 85 F6.3 --- alf21 ?=- Spectral index between W2 and W1 bands
86- 90 F5.2 --- alf32 ?=- Spectral index between W3 and W2 bands
92- 96 F5.2 --- alf43 ?=- Spectral index between W4 and W3 bands
98-102 F5.2 --- alf41 ?=- Spectral index between W4 and W1 bands
104 A1 --- l_logLOH Limit flag for upper limit on logLOH (3)
105-108 F4.2 [Lsun] logLOH ?=- Measured isotropic OH line luminosity or
lower value of interval (2)
109 A1 --- --- [-]
110-113 F4.2 [Lsun] logOHu ? Upper value of logLOH interval
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Note (1): logνLν. The luminosity was derived from corresponding flux
density, which can be converted from the magnitude value using the published
(iso)zero values (http://wise2.ipac.caltech.edu/docs/release/prelim/expsup/figures/sec4_-3gt4.gif).
Note (2): which are taken from Darling & Giovanelli (2000AJ....119.3003D 2000AJ....119.3003D,
2001AJ....121.1278D 2001AJ....121.1278D, 2002AJ....124..100D 2002AJ....124..100D, Cat. J/AJ/124/100);
Fernandez et al. (2010AJ....139.2066F 2010AJ....139.2066F); Willett (2012, IAU Symp., 287, 345)
for table6.dat.
Note (3): The upper limit of OH maser luminosity was derived from their
non-detection spectra (Darling & Giovanelli 2000AJ....119.3003D 2000AJ....119.3003D,
2001AJ....121.1278D 2001AJ....121.1278D, 2002AJ....124..100D 2002AJ....124..100D, Cat. J/AJ/124/100) for table7.dat.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 04-Dec-2014