Dust attenuation in galaxies up to redshift similar or equal to 2

V. Buat (1)

1 LAM - Laboratoire d'Astrophysique de Marseille

We want to study dust attenuation at ultraviolet (UV) wavelengths at high redshift, where the UV is redshifted to the observed visible light wavelength range. In particular, we search for a bump at 2175 A. We use photometric data in the Chandra Deep Field South (CDFS), obtained in intermediate and broad band filters by the MUSYC project, to sample the UV rest-frame of 751 galaxies with 0.95 \textless z \textless 2.2. When available, infrared (IR) Herschel/PACS* data from the GOODS-Herschel project, coupled with Spitzer/MIPS measurements, are used to estimate the dust emission and to constrain dust attenuation. The spectral energy distribution of each source is fit using the CIGALE code dagger. The average attenuation curve found for our sample galaxies exhibits a UV bump whose amplitude is similar to that observed in the extinction curve of the LMC super-shell region. The slope of the average attenuation curve at UV wavelength is found steeper than that for local starburst galaxies. The amount of dust attenuation at UV wavelengths is found to increase with stellar mass and to decrease as UV luminosity increases.

Domaines: Astrophysique [astro-ph]

V. Buat. Dust attenuation in galaxies up to redshift similar or equal to 2. Earth Planets and Space, 2013, 65 (10), pp.1095--1100. ⟨10.5047/eps.2013.02.001⟩. ⟨hal-01434418⟩