Astronomy and Astrophysics, volume 397, 191-200 (2003/1-1)
Interstellar extinction in the open clusters towards galactic longitude around 130°.
PANDEY A.K., UPADHYAY K., NAKADA Y. and OGURA K.
Abstract (from CDS):
In this paper we present a detailed study of the intra-cluster reddening material in the young open clusters located around l∼130° using colour-excess diagrams and two-colour diagrams. The study supports the universality of the extinction curves for λ≥λJ, whereas for shorter wavelengths the curve depends upon the value of the Rcluster (total-to-selective absorption in the cluster region). The value of Rcluster in the case of NGC 654, NGC 869 and NGC 884 is found to be normal, whereas the value of Rcluster in the cluster regions NGC 1502 and IC 1805 indicates an anomalous reddening law in these regions. In the case of NGC 1502 the value of Rcluster is found to be lower (2.57±0.27) whereas in the case of IC 1805 it is higher (3.56±0.29) than the normal value of 3.1. Although the intra-cluster material indicates a higher value of Rcluster in the NGC 663 region, the error in the estimation of Rcluster is too large to conclude anything. It is also found that the extinction process in the U band in the case of NGC 663 seems to be less efficient, whereas in the case of NGC 869 the process is more efficient.
ISM: dust, extinction - ISM: general - open clusters and associations: general