Peering into the heart of the giant molecular cloud G148.24+00.41: a deep near-infrared view of the newly hatched cluster FSR 655

Abstract

We present a detailed near-infrared study of an embedded cluster located in the hub of the giant molecular cloud G148.24+00.41 of mass ∼105M⊙, with the TANSPEC instrument mounted on the 3.6 m Devasthal Optical Telescope. The hub is located near the geometric center of the cloud and represents its most massive clump. We studied the central 2 pc × 2 pc area of the hub with 5σ limiting magnitudes of 20.5, 20.1, and 18.6 mag in the J, H, and Ks bands, respectively. Using the Ks-band luminosity function and comparing it with the synthetic clusters, we obtained the age of the cluster as ∼0.5 Myr, which was found to corroborate well with the visual extinction versus the age of nearby embedded clusters. We find that the present mass of the cluster is around ∼180 M⊙, and the cluster is currently forming stars at a rate of ∼330 M⊙ Myr−1, with an efficiency of ∼20%. The cluster is connected to an extended gas reservoir through a filamentary network; thus, we hypothesize that the cluster has the potential to become a richer cluster in a few Myr of time.