NIRI SV observation 7

NIRI and Acquisition Camera imaging observations of a well chosen globular cluster through the broad-band B, V, J, and K filters will be obtained. These observations, which should be done in the best possible seeing, will test 1) image quality over the widest possible field as a function of wavelength, 2) linearity of the Aquisition Camera CCD and the IR array systems as a function of background levels and exposure times, 3) quality of the calibrations and photmetric reduction techniques, and 4) astrometry of the imaging system.The high quality of the images, and good calibration would allow the following science: 1) a detailed study of the stellar luminosity function in different wavebands leading to a mass function and constraints on the mass-luminosity relation, 2) a measurement of mass segregation down to very low mass stars, 3) a search for white dwarfs which constrain the distance to the cluster, and 4) a well-defined turn-off and horizontal branch location and morphology which could improve the age estimate.