Extinction radial profiles of M83 from GALEX UV imaging

Samuel Boissier (1, 2) , Armando Gil de Paz (1) , B. F. Madore (1) , A. Boselli (3) , V. Buat (3) , D. Burgarella (3) , P. G. Friedman (4) , T. A. Barlow (4) , L. Bianchi (5) , Y. -I. Byun (6) , José Donas (3) , K. Forster (4) , T. M. Heckman (7) , P. N. Jelinsky (8) , Y. -W. Lee (6) , R. F. Malina (3) , D. C. Martin (4) , B. Milliard (3) , P. Morrissey (4) , Susan Gale Neff (9) , Robert Michael Rich (10) , David Schiminovich (4) , O. H. W. Siegmund (8) , Todd Small (4) , Alex Szalay (7) , Ted Wyder (4) , B. Welsh (8)

1 IAP - Institut d'Astrophysique de Paris
2 Observatories [Carnegie Institution]
3 LAM - Laboratoire d'Astrophysique de Marseille
4 CALTECH - California Institute of Technology
5 CAS - Center for Astrophysical Sciences [Baltimore]
6 Center for Space Astrophysics [Seoul]
7 Department of Physics and Astronomy [Baltimore]
8 SSL - Space Sciences Laboratory [Berkeley]
9 Laboratory for Astronomy and Solar Physics
10 Department of Physics and Astronomy [UCLA Los Angeles]

We use the far-UV (FUV) and near-UV (NUV) images of M83 obtained by GALEX to compute the radial profile of the UV spectral slope in the star forming disk. We briefly present a model of its chemical evolution which allows us to obtain realistic intrinsic properties of the stellar populations. Using corollary data, we also compute the profiles of H-alpha/H-beta and of the total IR (TIR) to FUV ratio. Both data and model are used to estimate and compare the extinction gradients at the FUV wavelength obtained from these various indicators. We discuss the implications for the determination of the star formation rate.

Domaines: Cosmologie et astrophysique extra-galactique [astro-ph.CO]

Samuel Boissier, Armando Gil de Paz, B. F. Madore, A. Boselli, V. Buat, et al.. Extinction radial profiles of M83 from GALEX UV imaging. The Astrophysical journal letters, 2005, 619L, pp.83B. ⟨10.1086/423668⟩. ⟨hal-00012836⟩