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Dust attenuation up to z~2 in the AKARI North Ecliptic Pole Deep Field

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 نشر من قبل Veronique Buat
 تاريخ النشر 2015
  مجال البحث فيزياء
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(Abridged) We aim to study the evolution of dust attenuation in galaxies selected in the IR in the redshift range in which they are known to dominate the star formation activity in the universe. The comparison with other measurements of dust attenuation in samples selected using different criteria will give us a global picture of the attenuation at work in star-forming galaxies and its evolution with redshift. Using multiple filters of IRC instrument, we selected more than 4000 galaxies from their rest-frame emission at 8 microns, from z~0.2 to 2$. We built SEDs from the rest-frame UV to the far-IR by adding data in the optical-NIR and from GALEX and Herschel surveys. We fit SEDs with the physically-motivated code CIGALE. We test different templates for AGNs and recipes for dust attenuation and estimate stellar masses, SFRs, amount of dust attenuation, and AGN contribution to the total IR luminosity. The AGN contribution to the total IR luminosity is found to be on average approximately 10% with a slight increase with redshift. Dust attenuation in galaxies dominating the IR luminosity function is found to increase from z=0 to z=1 and to remain almost constant from z=1 to z=1.5. Conversely, when galaxies are selected at a fixed IR luminosity, their dust attenuation slightly decreases as redshift increases but with a large dispersion. The attenuation in our mid-IR selected sample is found ~ 2 mag higher than that found globally in the universe or in UV and Halpha line selections in the same redshift range. This difference is well explained by an increase of dust attenuation with the stellar mass, in global agreement with other recent studies. Starbursting galaxies do not systematically exhibit a high attenuation

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