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Large-scale star formation in the Magellanic Clouds

Jochen M. Braun
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Abstract

In this contribution I will present the current status of our project of stellar population analyses and spatial information of both Magellanic Clouds (MCs). The Magellanic Clouds - especially the LMC with its large size and small depth (<300pc) - are suitable laboratories and testing ground for theoretical models of star formation. With distance moduli of 18.5 and 18.9mag for the LMC and SMC, respectively, and small galactic extinction, their stellar content can be studied in detail from the most massive stars of the youngest populations (<25Myr) connected to H-alpha emission down to the low mass end of about 1/10 of a solar mass. Based on broad-band photometry (U,B,V) I present results for the supergiant shell (SGS) SMC1, some regions at the LMC east side incl. LMC2 showing different overlapping young populations and the region around N171 with its large and varying colour excess, and LMC4. This best studied SGS shows a coeval population aged about 12Myr with little age spread and no correlation to distance from LMC4's centre. I will show that the available data are not compatible with many of the proposed scenarios like SSPSF or a central trigger (like a cluster or GRB), while a large-scale trigger like the bow-shock of the rotating LMC can do the job.

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Jochen M. Braun. 2001-08-03. Large-scale star formation in the Magellanic Clouds. https://arxiv.org/abs/astro-ph/0108056

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