CCD Photometry of M15

A. Ruelas-Mayorga, L. J. Sánchez, G. Herrera, A. Nigoche-Netro


We present CCD observations of the galactic globular cluster M15, in the B and V lters. The cluster was reasonably covered, except in its northern region where our observations present a gap. We obtained a Hertzsprung-Russell (HR) diagram for each region observed, and later we produced a combined HR diagram containing more than 3000 stars. We generate a clean Colour Magnitude Diagram (CMD) and a Super Fiducial Line (SFL). Application of several methods and isochrone fitting leads us to obtain values for the metallicity [Fe/H]M15 ~ -2.16 ± 0.10, the reddening E(B - V )M15 ~ 0:11 ± 0.03, and a distance
modulus of [(m - M)0]M15 ~ 15:03.


Galaxy: halo; globular clusters: general; globular clusters: individual (NGC 7078); techniques: photometric

Full Text:

PDF (Español)