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Extinction radial profiles of M83 from GALEX UV imaging

S. Boissier·A. Gil de Paz·B. F. Madore·A. Boselli·V. Buat·D. Burgarella·P. G. Friedman·T. A. Barlow·L. Bianchi·Y. -I. Byun·J. Donas·K. Forster·T. M. Heckman·P. N. Jelinsky·Y. -W. Lee·R. F. Malina·D. C. Martin·B. Milliard·P. Morrissey·S. G. Neff·R. M. Rich·D. Schiminovich·O. H. W. Siegmund·T. Small·A. S. Szalay·Barry Y. Welsh·T. K. Wyder
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Abstract

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.

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S. Boissier, A. Gil de Paz, B. F. Madore, A. Boselli, V. Buat, D. Burgarella, P. G. Friedman, T. A. Barlow, L. Bianchi, Y. -I. Byun, J. Donas, K. Forster, T. M. Heckman, P. N. Jelinsky, Y. -W. Lee, R. F. Malina, D. C. Martin, B. Milliard, P. Morrissey, S. G. Neff, R. M. Rich, D. Schiminovich, O. H. W. Siegmund, T. Small, A. S. Szalay, Barry Y. Welsh, T. K. Wyder. 2004-11-14. Extinction radial profiles of M83 from GALEX UV imaging. https://doi.org/10.1086/423668

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