Radial Velocity and Abundance Properties of Five Open Clusters Based on SDSS DR7

We present metallicities and radial velocities for five old open clusters (NGC 6791, NGC 2420, NGC 2682, NGC 2158, NGC 7789) using data from the SDSS DR7. The radial velocities are used to calculate cluster membership probabilities for stars in each cluster region. NGC 6791, NGC 2420, NGC 2682, NGC 2158 and NGC 7789 are found to have a mean metallicity [Fe/H]= +0.08 +/- 0.09, -0.38 +/- 0.11, -0.08 +/- 0.04, -0.41 +/- 0.14 and -0.18 +/- 0.13 dex(s.d.), respectively. The mean radial velocities for these clusters are Vr = -45.9 +/- 0.2, +76.1 +/- 0.2, +35.0 +/- 0.2, +26.9 +/- 0.2 and -48.2 +/- 0.2 km s(-1), respectively. We have compared our results with the values from literatures, found that our metallicity of NGC 6791 is significantly underestimated (by about 0.3 dex) and our radial velocities of the open clusters agree well with the values derived based on high-resolution spectroscopy.