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arXiv · 1411.3385

Star clusters in a nuclear star-forming ring: The disappearing string of pearls

Petri Vaisanen·Sudhanshu Barway·Zara Randriamanakoto
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Abstract

An analysis of the star cluster population in a low-luminosity early type galaxy, NGC 2328, is presented. The clusters are found in a tight star-forming nuclear spiral/ring pattern and we also identify a bar from structural 2D decomposition. These massive clusters are forming very efficiently in the circum-nuclear environment, they are young, possibly all less than 30 Myr of age. The clusters indicate an azimuthal age gradient, consistent with a "pearls-on-a-string" formation scenario suggesting bar driven gas inflow. The cluster mass function has a robust down-turn at low masses at all age bins. Assuming clusters are born with a power-law distribution, this indicates extremely rapid disruption at time-scales of just several Myr. If found to be typical, it means that clusters born in dense circum-nuclear rings do not survive to become old globular clusters in non-interacting systems.

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Petri Vaisanen, Sudhanshu Barway, Zara Randriamanakoto. 2014-11-12. Star clusters in a nuclear star-forming ring: The disappearing string of pearls. https://doi.org/10.1088/2041-8205%2F797%2F2%2Fl16

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