The stellar content of H72.97-69.39, a potential super star cluster in the making

TL;DR

This study characterizes a potential super star cluster in the Large Magellanic Cloud using near-infrared imaging, revealing its stellar content, ongoing star formation, and its status as a super star cluster candidate.

Contribution

It provides detailed near-infrared observations and analysis of a candidate super star cluster, including its stellar population, dust extinction, and molecular gas content, highlighting its potential as a super star cluster in formation.

Findings

Stellar mass estimated at least 10,000 Msun.

Ongoing star formation indicated by molecular gas and embedded stars.

High dust extinction up to A_K of 3 observed.

Abstract

Young Massive Clusters (YMCs) and Super Star Clusters (SSCs) represent an extreme mode of star formation. Far-infrared imaging of the Magellanic Clouds has identified one potential embedded SSC, HSO BMHERICC J72.971176-69.391112 (HH in short), in the south-west outskirts of the Large Magellanic Cloud. We present Gemini Flamingos 2 and GSAOI near-infrared imaging of a 3'x3' region around HH in order to characterize the stellar content of the cluster. The stellar content is probed down to 1.5 Msun. We find substantial dust extinction across the cluster region, extending up to A_K of 3. Deeply embedded stars are associated with ALMA-detected molecular gas suggesting that star formation is ongoing. The high spatial resolution of the GSAOI data allows identification of the central massive object associated with the 13CO ALMA observations and to detect fainter low-mass stars around the H30alpha ALMA source. The morphology of the molecular gas and the nebulosity from adjacent star formation suggest they have interacted covering a region of several pc. The total stellar content in the cluster is estimated from the intermediate- and high-mass stellar content to be at least 10000 Msun, less than R136 with up to 100 000 Msun within 4.7 pc radius, but places it in the regime of a super star cluster. Based on the extinction determination of individual stars we estimate a molecular gas mass in the vicinity of HH of 6600 Msun, suggesting more star formation can be expected.