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arXiv · 1702.03108

The Tarantula Nebula as a template for extragalactic star forming regions from VLT/MUSE and HST/STIS

P A Crowther·S M Caballero-Nieves·N Castro·C J Evans
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Abstract

We present VLT/MUSE observations of NGC 2070, the dominant ionizing nebula of 30 Doradus in the LMC, plus HST/STIS spectroscopy of its central star cluster R136. Integral Field Spectroscopy (MUSE) and pseudo IFS (STIS) together provides a complete census of all massive stars within the central 30x30 parsec^2 of the Tarantula. We discuss the integrated far-UV spectrum of R136, of particular interest for UV studies of young extragalactic star clusters. Strong HeII 1640 emission at very early ages (1-2 Myr) from very massive stars cannot be reproduced by current population synthesis models, even those incorporating binary evolution and very massive stars. A nebular analysis of the integrated MUSE dataset implies an age of ~4.5 Myr for NGC 2070. Wolf-Rayet features provide alternative age diagnostics, with the primary contribution to the integrated Wolf-Rayet bumps arising from R140 rather than the more numerous H-rich WN stars in R136. Caution should be used when interpreting spatially extended observations of extragalactic star-forming regions.

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P A Crowther, S M Caballero-Nieves, N Castro, C J Evans. 2017-02-10. The Tarantula Nebula as a template for extragalactic star forming regions from VLT/MUSE and HST/STIS. https://doi.org/10.1017/s1743921317002484

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