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Recent star formation in nearby galaxies from GALEX imaging:M101 and M51

Luciana Bianchi·D. Thilker·D. Burgarella·P. Friedman·C. Hoopes·S. Boissier·A. Gil de Paz·T. Barlow·Y. -I. Byun·J. Donas·K. Forster·T. Heckman·P. Jelinsky·Y-W Lee·B. Madore·R. Malina·C. Martin·B. Milliard·P. Morrissey·S. Neff·M. Rich·D. Schiminovich·O. Siegmund·T. Small·A. Szalay·B. Welsh·T. Wyder
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Abstract

The GALEX (Galaxy Evolution Explorer) Nearby Galaxies Survey is providing deep far-UV and near-UV imaging for a representative sample of galaxies in the local universe. We present early results for M51 and M101, from GALEX UV imaging and SDSS optical data in five bands. The multi-band photometry of compact stellar complexes in M101 is compared to population synthesis models, to derive ages, reddening, reddening-corrected luminosities and current/initial masses. The GALEX UV photometry provides a complete census of young compact complexes on a approximately 160pc scale. A galactocentric gradient of the far-UV - near-UV color indicates younger stellar populations towards the outer parts of the galaxy disks, the effect being more pronounced in M101 than in M51.

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Luciana Bianchi, D. Thilker, D. Burgarella, P. Friedman, C. Hoopes, S. Boissier, A. Gil de Paz, T. Barlow, Y. -I. Byun, J. Donas, K. Forster, T. Heckman, P. Jelinsky, Y-W Lee, B. Madore, R. Malina, C. Martin, B. Milliard, P. Morrissey, S. Neff, M. Rich, D. Schiminovich, O. Siegmund, T. Small, A. Szalay, B. Welsh, T. Wyder. 2004-11-15. Recent star formation in nearby galaxies from GALEX imaging:M101 and M51. https://doi.org/10.1086/422685

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