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Description
We present Spitzer IRAC, NOAO 2.1m Flamingos, Keck NIRC, and FCRAO SEQUOIA observations of the massive star-forming complex S254-S258, covering an area of 25'x20'. Using a combination of the IRAC and NIR data, we identify and classify the young stellar objects (YSOs) in the complex. We detect 510 sources with near- or mid-IR excess, and we classify 87 Class I and 165 Class II sources. The YSOs are found in clusters surrounded by isolated YSOs in a low-density distributed population. The ratio of clustered to total YSOs is 0.8. We identify six new clusters in the complex. One of them, G192.63-00, is located around the ionizing star of the HII region S255. We hypothesize that the ionizing star of S255 was formed in this cluster. We also detect a southern component of the cluster in HII region S256. The cluster G192.54-0.15, located inside HII region S254 has a V_LSR_ of 17km/s with respect to the main cloud, and we conclude that it is located in the background of the complex. The structure of the molecular cloud is examined using ^12^CO, and ^13^CO, as well as a near-IR extinction map. The main body of the molecular cloud has V_LSR_ between 5 and 9km/s. The arc-shaped structure of the molecular cloud following the border of the HII regions and the high column density in the border of the HII regions support the idea that the material has been swept up by the expansion of the HII regions.
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