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We present in this paper the first near infrared study of the young open cluster NGC 2244, which is well known for its partially embedded nature in the Rosette Nebula. Based on the spatially complete 2 Micron All Sky Survey, the young OB cluster indicates apparent substructures. It is surprisingly resolved into a compact core that matches well the congregation of massive OB stars in the optical, a satellite cluster at a distance of 6.6 pc in its west and probably a major stellar aggregate resembling an arc in structure right below the core. This infrared study provides various new updates on its nature of the young open cluster, including its central position, physical scale and stellar population. A disk fraction of $sim 20.5pm2.8%$ is achieved for its members with masses above 0.8 $M_{odot}$. NGC 2244 is hence a unique example for the study of embedded clusters.
As part of the ongoing effort to characterize the low-mass (sub)stellar population in a sample of massive young clusters, we have targeted the ~2 Myr old cluster NGC 2244. The distance to NGC 2244 from Gaia DR2 parallaxes is 1.59 kpc, with errors of
The open cluster (OC) NGC 2453 is of particular importance since it has been considered to host the planetary nebula (PN) NGC 2452, however their distances and radial velocities are strongly contested. In order to obtain a complete picture of the fun
[abridged] How does a star cluster of more than few 10,000 solar masses form? We present the case of the cluster NGC 346 in the Small Magellanic Cloud, and its star-forming region N66, and we propose a scenario for its formation, based on observation
We present new H-band echelle spectra, obtained with the NIRSPEC spectrograph at Keck II, for the massive star cluster B in the nearby dwarf irregular galaxy NGC 1569. From spectral synthesis and equivalent width measurements we obtain abundances and
Information on globular clusters (GC) formation mechanisms can be gathered by studying the chemical signature of the multiple populations that compose these stellar systems. In particular, we are investigating the anticorrelations among O, Na, Al, an