J/A+A/551/A100 Panchromatic SED of Herschel sources (Berta+, 2013)
Panchromatic spectral energy distributions of Herschel sources.
Berta S., Lutz D., Santini P., Wuyts S., Rosario D., Brisbin D., Cooray A.,
Franceschini A., Gruppioni C., Hatziminaoglou E., Hwang H.S., Le Floc'h E.,
Magnelli B., Nordon R., Oliver S., Page M.J., Popesso P., Pozzetti L.,
Pozzi F., Riguccini L., Rodighiero G., Roseboom I., Scott D., Symeonidis M.,
Valtchanov I., Viero M., Wang L.
<Astron. Astrophys. 551, A100 (2013)>
=2013A&A...551A.100B 2013A&A...551A.100B
ADC_Keywords: Galaxies, IR ; Galaxies, optical ; Galaxies, Seyfert ;
Active gal. nuclei ; Energy distributions
Keywords: infrared: galaxies - galaxies: statistics - galaxies: star formation -
galaxies: active - galaxies: evolution
Abstract:
Combining far-infrared Herschel photometry from the PACS Evolutionary
Probe (PEP) and Herschel Multi-tiered Extragalactic Survey (HerMES)
guaranteed time programs with ancillary datasets in the GOODS-N,
GOODS-S and COSMOS fields, it is possible to sample the 8-500 micron
spectral energy distributions of galaxies with at least 7-10 bands.
Extending to the UV, optical, and near- infrared, the number of bands
increases up to 43. We reproduce the distribution of galaxies in a
carefully selected 10 restframe color space, based on this rich
data-set, using a superposition of multi-variate Gaussian modes. We
use this model to classify galaxies and build median spectral energy
distributions (SEDs) of each class, which are then fitted with a
modified version of the MAGPHYS code that combines stellar light,
emission from dust heated by stars and a possible warm dust
contribution heated by an Active Galactic Nucleus (AGN). The color
distribution of galaxies in each of the considered fields can be well
described with the combination of 6-9 classes, spanning a large range
of far- to near-IR luminosity ratios, as well as different strength of
the AGN contribution to bolometric luminosities. The defined Gaussian
grouping is used to identify rare or odd sources. The zoology of
outliers includes Herschel-detected ellipticals, very blue z∼1
Lyα-break galaxies, quiescent spirals, and torus-dominated AGN
with star formation. Out of these groups and outliers, a new template
library is assembled, consisting of 32 SEDs describing the intrinsic
scatter in the restframe UV-to-submm colors of infrared galaxies. This
library is tested against L(IR) estimates with and without Herschel
data included, and compared to eight other popular methods often
adopted in the literature. When implementing Herschel photometry,
these approaches produce L(IR) values consistent with each other
within a median absolute deviation of 10-20%, the scatter being
dominated more by fine tuning of the codes, rather than by the choice
of SED templates. Finally, the library is used to classify 24 micron
detected sources in PEP GOODS fields on the basis of AGN content,
L(60)/L(100) color and L(160)/L(1.6) luminosity ratio. AGN appear to
be distributed in M*-SFR along with all other galaxies, regardless of
the amount of infrared luminosity they are powering, with the tendency
to lie on the high SFR side of the "main sequence". The incidence of
warmer star-forming sources grows for objects with higher specific
star formation rates, and they tend to populate the "off-sequence"
region of the M*-SFR-z space.
File Summary:
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FileName Lrecl Records Explanations
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ReadMe 80 . This file
list.dat 69 32 List of available files
temp1p6/* . 32 Templates of galaxies normalised to 1.6um
tempLIR/* . 32 Templates of galaxies normalised at L(IR)=1L☉
tempM/* . 32 Templates of galaxies normalised at M*=10+10M☉
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Byte-by-byte Description of file: list.dat
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Bytes Format Units Label Explanations
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1- 17 A17 --- FileName Generic name of the file
19- 59 A41 --- Mod Type of galaxy
61- 63 A3 --- 1p6 Spectrum normalized to 1.6um
65- 67 A3 --- LIR Spectrum normalized to LIR=1L☉
69 A1 --- M Spectrum normalized to M*=10+10M☉
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Byte-by-byte Description of file: temp*/*
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Bytes Format Units Label Explanations
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1- 15 F15.5 0.1nm lambda [90/1949e+04] Wavelength
16- 30 E15.7 --- Flux Flux density S(lambda), normalized
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Acknowledgements:
Stefano Berta, berta(at)mpe.mpg.de
History:
* 01-Mar-2013: First on-line version
* 13-Jun-2016: Corrected spectra, from author
(End) Stefano Berta [MPE, Germany], Patricia Vannier [CDS] 13-Jun-2016