J/A+A/622/A132 Dust emission profiles of DustPedia galaxies (Mosenkov+, 2019)
Dust emission profiles of DustPedia galaxies.
Mosenkov A.V., Baes M., Bianchi S., Casasola V., Cassara L.P.,
Clark C.J.R., Davies J., De Looze I., De Vis P., Fritz J., Galametz M.,
Galliano F., Jones A.P., Lianou S., Madden S. C., Nersesian A.,
Smith M.W.L., Trcka A., Verstocken S., Viaene S., Vika M., Xilouris E.
<Astron. Astrophys. 622, A132 (2019)>
=2019A&A...622A.132M 2019A&A...622A.132M (SIMBAD/NED BibCode)
ADC_Keywords: Galaxies, nearby ; Galaxies, photometry
Keywords: galaxies: ISM - submillimetre: ISM - galaxies: structure
Abstract:
Most radiative transfer models assume that dust in spiral galaxies is
distributed exponentially. In this paper our goal is to verify this
assumption by analysing the two-dimensional large-scale distribution
of dust in galaxies from the DustPedia sample. For this purpose, we
have made use of Herschel imaging in five bands, from 100 to 500um, in
which the cold dust constituent is primarily traced and makes up the
bulk of the dust mass in spiral galaxies. For a subsample of 320 disc
galaxies, we successfully performed a simultaneous fitting with a
single Sersic model of the Herschel images in all five bands using the
multi-band modelling code GALFITM. We report that the Sersic index n,
which characterises the shape of the Sersic profile, lies
systematically below 1 in all Herschel bands and is almost constant
with wavelength. The average value at 250um is 0.67±0.37 (187
galaxies are fitted with n250≤0.75, 87 galaxies have
0.75<n250≤1.25, and 46 - with n250>1.25). Most observed profiles
exhibit a depletion in the inner region (at r<0.3-0.4 of the optical
radius r25) and are more or less exponential in the outer part. We
also find breaks in the dust emission profiles at longer distances
(0.5-0.6)r25 which are associated with the breaks in the optical and
near-infrared. We assumed that the observed deficit of dust emission
in the inner galaxy region is related to the depression in the radial
profile of the HI surface density in the same region because the
atomic gas reaches high enough surface densities there to be
transformed into molecular gas. If a galaxy has a triggered star
formation in the inner region (for example, because of a strong bar
instability, which transfers the gas inwards to the centre, or a
pseudobulge formation), no depletion or even an excess of dust
emission in the centre is observed.
Description:
Here we present the results from fitting the DustPedia galaxies with a
single Sersic model which assumes several free parameters: the total
magnitude, the effective radius, the Sersic index, the apparent axis
ratio, and the position angle. The fit is applied to the WISE W1
(3.4um) for the whole sample and Herschel (beyond 100um) data for a
subsample of 339 galaxies.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
fitw1.dat 59 875 The fit results as derived from the single
Sersic fitting of the WISE 3.4um data
fitw1s.dat 60 875 Supplementary data
fither.dat 205 339 The fit results as derived from the multiband
single Sersic fitting of the Herschel
100-500um data
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See also:
II/311 : WISE All-Sky Data Release (Cutri+ 2012)
J/A+A/609/A37 : 875 nearby galaxies multiwavelength photometry (Clark+, 2018)
J/ApJS/219/4 : S4G pipeline 4: multi-component decompositions (Salo+, 2015)
http://dustpedia.astro.noa.gr : DustPedia Home Page
Byte-by-byte Description of file: fitw1.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- Name Galaxy name
25- 30 F6.2 mag mtot [5.55/17.66]? Model magnitude WISE 3.4um
32- 38 F7.2 arcsec re [0.01/5606.11]? Effective radius
40- 45 F6.2 --- n [0.02/20.0]? Sersic index
47- 52 F6.2 --- q [0.01/1.0]? Axis ratio
54- 59 F6.1 deg PA [-89.8/90.0]? Position angle
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Byte-by-byte Description of file: fitw1s.dat
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Bytes Format Units Label Explanations
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1- 23 A23 --- Name Galaxy name
25- 30 F6.2 mag map [5.75/21.81]? Aperture magnitude WISE 3.4um (1)
32- 37 F6.2 [Lsun] logLum [1.49/10.8]? Log total luminosity (2)
39- 44 F6.2 [Msun] logMass [2.7/12.01]? Log stellar mass (3)
46- 50 F5.1 deg i [0.0/90.0]? Galaxy inclination (4)
52- 56 F5.1 --- T [-5.0/10.0]? Morphological type (5)
58- 60 F3.1 --- e_T [0.1/7.1]? Uncertainty of morphological type (5)
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Note (1): The total magnitude calculated within the master ellipse aperture
defined in Clark et al., 2018, Cat. J/A+A/609/A37.
Note (2): The total luminosity computed from map and best distance taken from
Clark et al., 2018, Cat. J/A+A/609/A37.
Note (3): It was calculated using the mass-to-light luminosity ratio
M*/LW3.4=0.65.
Note (4): It was calculated using the S4G decomposition results from Salo et
al., 2015, J/ApJS/219/4 or our single Sersic fitting in the WISE 3.4um band
(using the fit apparent axis ratio for the Hubble formula to calculate the
inclination), see the Appendix D for more details
Note (5): Quantities from HyperLEDA (http://leda.univ-lyon1.fr/).
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Byte-by-byte Description of file: fither.dat
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Bytes Format Units Label Explanations
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1- 10 A10 --- Name Galaxy name
12- 23 F12.8 Jy F100 [0.26/666.3]? Model flux in PACS 100um band
25- 30 F6.2 arcsec re100 [0.02/338.46]? Effective radius in
PACS 100um band
32- 36 F5.2 --- n100 [0.01/45.21]? Sersic index in PACS 100um band
38- 41 F4.2 --- q100 [0.07/0.98]? Axis ratio in PACS 100um band
43- 47 F5.1 deg PA100 [-89.1/90.0]? Position angle in
PACS 100um band
49- 60 F12.8 Jy F160 [0.36/853.58]? Model flux in PACS 160um band
62- 68 F7.2 arcsec re160 [0.05/4740.01]? Effective radius in
PACS 160um band
70- 74 F5.2 --- n160 [0.01/33.55]? Sersic index in PACS 160um band
76- 79 F4.2 --- q160 [0.07/0.98]? Axis ratio in PACS 160um band
81- 85 F5.1 deg PA160 [-89.1/90.0]? Position angle in PACS 160um band
87- 98 F12.8 Jy F250 [0.26/401.81]? Model flux in SPIRE 250um band
100-105 F6.2 arcsec re250 [0.05/381.04]? Effective radius in
SPIRE 250um band
107-111 F5.2 --- n250 [0.02/20.0]? Sersic index in SPIRE 250um band
113-116 F4.2 --- q250 [0.07/0.98]? Axis ratio in SPIRE 250um band
118-122 F5.1 deg PA250 [-89.1/90.0]? Position angle in SPIRE 250um band
124-135 F12.8 Jy F350 [0.195/188.08]? Model flux in SPIRE 350um band
137-143 F7.2 arcsec re350 [0.48/1758.74]? Effective radius in
SPIRE 350um band
145-149 F5.2 --- n350 [0.01/20.0]? Sersic index in SPIRE 350um band
151-154 F4.2 --- q350 [0.07/0.98]? Axis ratio in SPIRE 350um band
156-160 F5.1 deg PA350 [-89.1/90.0]? Position angle in SPIRE 350um band
162-172 F11.8 Jy F500 [0.09/72.83]? Model flux in SPIRE 500um band
174-180 F7.2 arcsec re500 [0.03/3679.21]? Effective radius in
SPIRE 500um band
182-186 F5.2 --- n500 [0.01/37.21]? Sersic index in SPIRE 500um band
188-191 F4.2 --- q500 [0.07/0.98]? Axis ratio in SPIRE 500um band
193-197 F5.1 deg PA500 [-89.1/90.0]? Position angle in SPIRE 500um band
199-205 F7.3 --- chi2nu [0.71/106.364]? Reduced chi2
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Acknowledgements:
Aleksandr Mosenkov, mosenkovAV(at)gmail.com
(End) Patricia Vannier [CDS] 04-Dec-2018