Near-Infrared Observations of the Massive Star Forming Region IRAS 23151+5912

Near-infrared images and K-band spectroscopy of the massive star-forming region IRAS 23151+5912 are presented. The JHK’ images reveal an embed-ded infrared cluster associated with infrared nebula, and the H(2.12μm) narrow-band image provides for the first time evidence of outflow activity associated withthe cluster. That the cluster is young can be shown by the high percentage ofinfrared excess sources and the outflow activity. We suggest an age of the clus-ter of ～ 10~6yr. Eight young stars are found in the bright nebular core aroundIRAS 23151+5912. By the color-magnitude diagrams of the cluster, we found fivehigh--mass YSOs and four intermediate-mass YSOs in the cluster. Eight Hemissionfeatures are discovered in the region with a scattered and non-axisymmetric distri-bution, indicating the existence of multiple outflows driven by the cluster. DiffuseHemission detected to the north and to the west of the cluster may result fromUV leakage of the cluster. Brγ, H, and CIV emission lines are