VRI Photometry of M67 for CCD Standardization at 2.3m VBT

Abstract

We present the results from CCD photometry in the V, R and I bands, of the ‘Dipper Asterism’ region of the open cluster Μ67 based on observations carried out at the prime focus of the 2.3 m Vainu Bappu Telescope of the Vainu Bappu Observatory, Kavalur. The CCD parameters like the system gain and the readout noise are measured using several flatfield frames taken through the standard I filter. The CCD chip is calibrated using the photometric standards in the field and linear colour transformation relations are derived. Also a few new VRI photometric measurements are reported for the members of the cluster.