'Astronomical Society of the Pacific Conference Series'
Abstract
Visual photometry at V and i has been obtained for five RR Lyrae variables in the extremely metal-poor globular cluster M92 and eight in the cluster M5, of intermediate metallicity, for use in a Baade-Wesselink analysis. The periods of these variables have been updated by combining observations of the current epoch with older data from the literature. Mean magnitudes are derived from the light curves. Infrared photometry at J and has also been obtained for two RR Lyrae variables in M92 and for four variables in the cluster M5. The data were obtained with a 58 x 62 pixel InSb array. The reduction and analysis techniques are discussed. Preliminary distance determinations using the〈M_v〉 —[Fe/H] relationship from the literature were derived as (m—M)_0 = 14.48 ± 0.04 for M92 and 14.25 ± 0.05 for M5, while preliminary distance determinations using the〈M_K〉— log(P) relationship were derived as 0.15 mag smaller
