J/MNRAS/439/1648 Subarcsecond mid-infrared atlas of local AGN (Asmus+, 2014)
The subarcsecond mid-infrared view of local active galactic nuclei:
I. The N- and Q-band imaging atlas.
Asmus D., Hoenig S.F., Gandhi P., Smette A., Duschl W.J.
<Mon. Not. R. Astron. Soc. 439, 1648 (2014)>
=2014MNRAS.439.1648A 2014MNRAS.439.1648A (SIMBAD/NED BibCode)
ADC_Keywords: Active gal. nuclei ; Atlases ; Galaxies, IR ; Galaxies, nearby ;
Galaxies, photometry ; Galaxies, Seyfert ; Photometry, infrared
Keywords: atlases - galaxies: active - galaxies: nuclei - infrared: galaxies
Abstract:
We present the first subarcsecond-resolution mid-infrared (MIR) atlas
of local active galactic nuclei (AGN). Our atlas contains 253 AGN with
a median redshift of z=0.016, and includes all publicly available MIR
imaging performed to date with ground-based 8-m class telescopes, a
total of 895 independent measurements. Of these, more than 60% are
published here for the first time. We detect extended nuclear emission
in at least 21% of the objects, while another 19% appear clearly
point-like, and the remaining objects cannot be constrained. Where
present, elongated nuclear emission aligns with the ionization cones
in Seyferts. Subarcsecond resolution allows us to isolate the AGN
emission on scales of a few tens of parsecs and to obtain nuclear
photometry in multiple filters for the objects. Median spectral energy
distributions (SEDs) for the different optical AGN types are
constructed and individual MIR 12 and 18um continuum luminosities are
computed. These range over more than six orders of magnitude. In
comparison to the arcsecond-scale MIR emission as probed by Spitzer,
the continuum emission is much lower on subarcsecond scales in many
cases. The silicate feature strength is similar on both scales and
generally appears in emission (absorption) in type I (II) AGN.
However, the polycyclic aromatic hydrocarbon emission appears weaker
or absent on subarcsecond scales. The differences of the MIR SEDs on
both scales are particularly large for AGN/starburst composites and
close-by (and weak) AGN. The nucleus dominates over the total emission
of the galaxy only at luminosities ≳1044erg/s. The AGN MIR atlas is
well suited not only for detailed investigation of individual sources
but also for statistical studies of AGN unification.
Description:
The Subarcsecond mid-infrared (MIR) atlas of local active galactic
nuclei (AGN) is a collection of all available N- and Q-band images
obtained at ground-based 8-meter class telescopes with public archives
(Gemini/Michelle, Gemini/T-ReCS, Subaru/COMICS, and VLT/VISIR). It
includes in total 895 images, of which 60% are perviously unpublished.
These correspond to 253 local AGN with a median redshift of 0.016. The
atlas contains the uniformly processed and calibrated images and
nuclear photometry obtained through Gauss and PSF fitting for all
objects and filters. This also includes measurements of the nuclear
extensions. In addition, the classifications of extended emission (if
present) and derived nuclear monochromatic 12 and 18 micron continuum
fluxes are available. Finally, flux ratios with the circumnuclear MIR
emission (measured by Spitzer) and total MIR emission of the galaxy
(measured by IRAS) are presented. The observations have been taken in
the mid-infrared (N-band, 7-13micron, and Q-band, 17-20micron) between
2003-12-02 and 2011-06-15 and cover the whole sky. The objects have
redshifts between -0.0001 and 0.3571.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
table1.dat 134 253 Basic object properties and nuclear 12 & 18um
continuum fluxes/ratios
table2.dat 276 901 Photometric parameters for all nuclear
measurements
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See also:
J/ApJ/610/128 : NIR colors of hard X-ray-selected AGN (Watanabe+, 2004)
J/ApJ/680/130 : Mid-IR colors of AGNs in the MUSYC ECDF-S (Cardamone+, 2008)
J/ApJ/705/14 : Seyfert galaxies in the mid-IR (Deo+, 2009)
J/ApJ/725/2270 : Mid-IR emission lines in AGNs (Pereira-Santaella+, 2010)
J/ApJS/208/24 : Spitzer MIR AGN survey. I. (Lacy+, 2013)
Byte-by-byte Description of file: table1.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- Name Common object name
25- 34 F10.6 deg RAdeg Right ascension (J2000.0)
36- 45 F10.6 deg DEdeg Declination (J2000.0)
47- 53 F7.4 --- z Redshift
55- 60 F6.1 Mpc Dist Distance (1)
62- 70 A9 --- Class Optical classification (2)
72 A1 --- Doubt [F/T] Uncertain AGN flag (3)
74- 76 I3 --- BATID ? BAT ID from 9-month catalog (from Winter et
al., 2009ApJ...690.1322W 2009ApJ...690.1322W)
78- 83 A6 --- ExtCl Nuclear MIR extension classification (4)
85 A1 --- l_F12um [F/T] Limit flag for the nuclear 12um flux (5)
87- 93 F7.1 mJy F12um Nuclear 12um restframe continuum flux (6)
95-100 F6.1 mJy e_F12um ? 1-sigma uncertainty of the 12um flux
102 A1 --- l_F18um [F/T] Limit flag for the nuclear 18um flux (7)
104-110 F7.1 mJy F18um ? Nuclear 18um restframe continuum flux
112-117 F6.1 mJy e_F18um ? 1-sigma uncertainty of the 18um continuum flux
119-122 I4 pc Dunr Size constraint on unresolved emission (8)
124-127 F4.2 --- N/I ? Flux ratio of nuclear to intermediate scale (9)
129-134 F6.4 --- N/L ? Flux ratio of nuclear to large scale (10)
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Note (1): Mostly redshift-based luminosity distance, corrected for the Earth's
motion relative to the cosmic microwave background reference frame with
H0=67.3, Omegam=0.315, and Omegavac=0.685, or redshift-independent
distance (See App. B of the paper).
Note (2): References for the collected optical AGN classifications are given in
App. B of the paper.
Note (3): If 'T' (True), the presence of an AGN is uncertain (App. B of the
paper).
Note (4): nuclear morphology at subarcsecond resolution as follows:
- = point-like
o = possibly extended
? = unknown extension
circ. = spherical extended
ellip. = elliptical and bar-like extended
spir. = spiral-like extended
comp. = complex extended emission
Note (5): if 'T' (True) the object was not detected at 12um. In that case, F12um
represents the 3-sigma upper limit.
Note (6): nuclear subarcsecond-scale monochromatic flux density at restframe
12micron.
Note (7): if 'T' (True) the object was not detected at 18um. In that case, F18um
represents the 3-sigma upper limit.
Note (8): size constraint on the nuclear unresolved emission in pc, which is set
equal to the minimum PSF FWHM (major axis) measured for the object.
Note (9): The in Spitzer/IRS unresolved flux component is used as measure for
the intermediate-scale emission.
Note (10): The IRAS 12micron flux is used as measure for the large-scale
emission.
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Byte-by-byte Description of file: table2.dat
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Bytes Format Units Label Explanations
--------------------------------------------------------------------------------
1- 23 A23 --- Name Common object name
25- 34 F10.6 deg RAdeg Right ascension (J2000.0)
36- 45 F10.6 deg DEdeg Declination (J2000.0)
47- 53 A7 --- Filter Filter name
55- 59 F5.2 um lambc Filter central wavelength (observing frame)
61- 64 F4.2 um HWHM Filter half-width-half-maximum
66- 73 A8 --- Inst Instrument used to obtain data
75- 79 F5.3 arcsec/pix Scale Pixel size of field of view
81- 84 I4 s ExpTim Total exposure time on-source
86- 89 A4 --- ChpMod Chop & nod mode
91- 92 I2 arcsec ChpThw Chop throw
94- 97 I4 deg ChpAng Chop angle East of North
99-102 I4 deg InsRot Instrument rotation angle on sky, W of N
104-119 A16 --- ProgID Observation programme ID
121-132 A12 --- CalStr Calibrator star name
134-149 A16 --- CalDat Calibrator star obervational date
151-159 F9.3 d CalMJD ? Calibrator star obervational MJD
161-176 A16 --- ObsDat Obervational date
178-186 F9.3 d ObsMJD Obervational MJD
188-195 F8.5 mJy/ct CnvFac Conversion factor measured from the Cal
197-203 F7.5 mJy/ct e_CnvFac 1-sigma uncertainty of the Conv. factor
205-214 F10.1 mJy CalFlx ? Calibrator star flux
216 A1 --- l_FGau [F/T] Limit flag on the Gauss flux (1)
218-224 F7.1 mJy FGau Nuclear flux from 2D Gauss fitting
226-231 F6.1 mJy e_FGau ? 1-sigma uncertainty of the Gauss flux
233 A1 --- l_FPSF [F/T] Limit flag on the PSF flux (2)
235-241 F7.1 mJy FPSF Nuclear flux from PSF scaling
243-248 F6.1 mJy e_FPSF ? 1-sigma uncertainty of the PSF flux
250-253 F4.2 arcsec CalMaj ? Calibrator Star major axis FWHM
255-258 F4.2 arcsec CalMin ? Calibrator Star minor axis FWHM
260-262 I3 deg CalPA ? Calibrator Star position angle E of N
264-267 F4.2 arcsec amaj ? Major axis FWHM (constrained to ≤1arcsec)
269-272 F4.2 arcsec bmaj ? Minor axis FWHM (constrained to ≤1arcsec)
274-276 I3 deg PA ? Position angle of Gauss fit East of North
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Note (1): if 'T' (True) the object was not detected. In that case, FGau
represents the 3-sigma upper limit.
Note (2): if 'T' (True) the object was not detected or no matching Calibrator
Star was available. In that case, FPSF represents the 3-sigma upper limit.
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Acknowledgements:
Daniel Asmus, asmus(at)mpifr.de
References:
Asmus et al. Paper II. 2015MNRAS.454..766A 2015MNRAS.454..766A Cat. J/MNRAS/454/766
Asmus et al. Paper III. 2016ApJ...822..109A 2016ApJ...822..109A Cat. J/ApJ/822/109
Isbell et al. Paper IV. 2021ApJ...910..104I 2021ApJ...910..104I Cat. J/ApJ/910/104
(End) Daniel Asmus [MPIfR, Germany], Patricia Vannier [CDS] 12-Mar-2014