J/A+A/591/A136 Galaxies and QSOs FIR size and surface brightness (Lutz+, 2016)
The far-infrared emitting region in local galaxies and QSOs:
Size and scaling relations.
Lutz D., Berta S., Contursi A., Forster Schreiber N.M., Genzel R.,
Gracia-Carpio J., Herrera-Camus R., Netzer H., Sturm E., Tacconi L.J.,
Tadaki K., Veilleux S.
<Astron. Astrophys., 591, A136 (2016)>
=2016A&A...591A.136L 2016A&A...591A.136L (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; QSOs ; Infrared sources
Keywords: Galaxy: structure - galaxies: starburst - galaxies: active
Abstract:
We use Herschel 70 to 160µm images to study the size of the
far-infrared emitting region in about 400 local galaxies and quasar
(QSO) hosts. The sample includes normal "main-sequence"
star-forming galaxies, as well as infrared luminous galaxies and
Palomar-Green QSOs, with different levels and structures of star
formation. Assuming Gaussian spatial distribution of the far-infrared
(FIR) emission, the excellent stability of the Herschel point spread
function (PSF) enables us to measure sizes well below the PSF width,
by subtracting widths in quadrature. We derive scalings of FIR size
and surface brightness of local galaxies with FIR luminosity, with
distance from the star-forming main-sequence, and with FIR color.
Luminosities LFIR∼1011L☉ can be reached with a variety of
structures spanning 2dex in size. Ultraluminous
LFIR∼1012L☉ galaxies far above the main-sequence
inevitably have small Re,70∼0.5kpc FIR emitting regions with large
surface brightness, and can be close to optically thick in the FIR on
average over these regions. Compared to these local relations, first
ALMA sizes for the dust emission regions in high redshift galaxies,
measured at somewhat longer rest wavelengths, suggest larger sizes at
the same IR luminosity. We report a remarkably tight relation with
0.15dex scatter between FIR surface brightness and the ratio of [CII]
158µm emission and FIR emission - the so-called [CII]-deficit is
more tightly linked to surface brightness than to FIR luminosity or
FIR color. Among 33 z≤0.1 PG QSOs with typical
LFIR/LBol,AGN∼0.1, 19 have a measured 70µm half light radius,
with median Re,70=1.1kpc. This is consistent with the FIR size for
galaxies with similar LFIR but lacking a QSO, in accordance with a
scenario where the rest FIR emission of these types of QSOs is, in
most cases, due to host star formation.
Description:
We use 70, 100, and 160um images from scan maps obtained with PACS on
board Herschel, collecting archival data from various projects. In
order to cover a wide range of galaxy properties, we first obtain an
IR-selected local sample ranging from normal galaxies up to
(ultra)luminous infrared galaxies. For that purpose, we searched the
Herschel archive for all cz≥2000km/s objects from the IRAS Revised
Bright Galaxy Sample (RBGS, Sanders et al., 2003, Cat. J/AJ/126/1607).
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
tablea1.dat 98 399 Far-infrared size and surface brightness of
galaxies and QSOs
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See also:
J/AJ/126/1607 : IRAS Revised Bright Galaxy Sample (Sanders+, 2003)
Byte-by-byte Description of file: tablea1.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- Name Target name
19- 26 F8.4 deg RAdeg Right ascension (J2000) (1)
28- 35 F8.4 deg DEdeg Declination (J2000) (1)
37 A1 --- Cl [G/Q] Class, Galaxy (G) or QSO (Q)
39 A1 --- Mo [D] Morphology (2)
41- 45 F5.3 kpc/arcsec Scale Scale for the adopted distance and
cosmology
47 A1 --- l_Re70 Limit flag on Re70
48- 52 F5.3 kpc Re70 ? Far-infrared half light radii
at 70um (3)
54- 58 F5.3 kpc e_Re70 ? rms uncertainty on Re70
60 A1 --- l_Re100 Limit flag on Re100
61- 66 F6.3 kpc Re100 ? Far-infrared half light radii
at 100um (3)
68- 72 F5.3 kpc e_Re100 ? rms uncertainty on Re100
74 A1 --- l_Re160 Limit flag on Re160
75- 80 F6.3 kpc Re160 ? Far-infrared half light radii
at 160um (3)
82- 86 F5.3 kpc e_Re160 ? rms uncertainty on Re160
88 A1 --- l_log(SFIR) Limit flag on log(SFIR)
89- 93 F5.2 [Lsun/kpc+2] log(SFIR) ? Surface brightness of the 40-120um
far-infrared emission
95- 98 F4.2 [Lsun/kpc+2] e_log(SFIR) ? rms uncertainty on log(SFIR)
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Note (1): Far-infrared source position, as measured from the Gaussian fits
Note (2): D denotes a double source with potentially inflated fitted size
Note (3): Missing entries for a given band indicate photometric S/N<10 or band
not observed. Half light radii are based on subtracting in quadrature observed
width and PSF width. The errors are statistical and do not include systematics
due to the non-gaussianity of the real source structure and PSF.
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History:
From electronic version of the journal
(End) Patricia Vannier [CDS] 23-Aug-2016