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The population in the background of open clusters: Tracer of the Norma-Cygnus arm

A. K. Pandey·S. Sharma·K. Ogura
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Abstract

We present colour-magnitude diagrams of open clusters, located in the range $112^\circ < l < 252^\circ$, manifesting stellar populations in the background of clusters. Some of the populations are found to be located beyond the Perseus arm and may be the part of Norma-Cygnus (outer) arm. The outer arm seems to be continued from $l\sim120^\circ$ to $l\sim235^\circ$. The background populations follow the downward warp of the Galactic plane around $l\sim240^\circ$.

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A. K. Pandey, S. Sharma, K. Ogura. 2006-08-31. The population in the background of open clusters: Tracer of the Norma-Cygnus arm. https://doi.org/10.1111/j.1365-2966.2006.11015.x

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