We present a new photometric study of the globular cluster NGC288 in Stromgren u, v, b, y, and Hβ system. This cluster is known to have an intermediate metallicity but its color-magnitude diagram has a pure blue horizontal branch, which is a signature of metal poor stellar population. We compare our dataset with Bergbusch's (1993) in both field size and CMD to see whether different photometry system would determine the same physical parameters of a cluster. Demarque and Yi's isochrones (1996, private communication) were applied to Bergbusch's dataset, and we obtained distance modulus of (m - M) = 14.9 ± 0.2, color excess of E(B - V) = 0.03, and age of 1.5±3 Gyr. Vandenberg's (1985) isochrones for Stromgren system were also applied to Bergbusch's and our data. We find that the isochrone fits to different photometric systems give rather in consist ant solutions. The source of this discrepancy may become clear when the Demarque and Yi's isochrones for Johnson system are converted to those of Stromgren system. We note that Kurucz model atmospheres provide a useful ground for this conversion work as well as theoretical study of Stromgren characteristics of globular cluster stars.

• ROSIE CHANG-HUI CHEN(Institute of Astronomy National Central University)
• PHILLIP K. Lu(Institute of Astronomy National Central University)
• WEAN-SHUN TSAY(Institute of Astronomy National Central University)