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arXiv · 1909.09033

Discrete star formation events in the central Bar of the Small Magellanic Cloud

A. Strantzalis·D. Hatzidimitriou·A. Zezas·V. Antoniou·S. Lianou·S Tsilia
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Abstract

We present the results of the photometric analysis of a large part of the main body of the Small Magellanic Cloud. Using the 6.5m Magellan Telescope at the Las Campanas Observatory in Chile, we have acquired deep B and I images in four fields (0.44 degree each in diameter), yielding accurate photometry for 1,068,893 stars down to 24th magnitude, with a spatial resolution of 0.20 arcsec per pixel. Colour-magnitude diagrams and (completeness corrected) luminosity functions have been constructed, yielding significant new results that indicate at least two discrete star formation events over a period from 2.7 to 4 Gyr ago. Also, we have derived star formation rates as a function of look back time and have found enhancements of SF between 4-6 Gyr and at younger ages.

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A. Strantzalis, D. Hatzidimitriou, A. Zezas, V. Antoniou, S. Lianou, S Tsilia. 2019-09-19. Discrete star formation events in the central Bar of the Small Magellanic Cloud. https://doi.org/10.1093/mnras/stz2540

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