Deep Hubble Space Telescope WFPC2 Photometry of NGC 288. II. The Main-Sequence Luminosity Function

The main-sequence luminosity function (LF) of the Galactic globular cluster NGC 288 has been obtained using deep Wide Field Planetary Camera 2 photometry. We have employed a new method to correct for completeness and fully account for bin-to-bin migration due to blending and/or observational scatter. The effect of the presence of binary systems in the final LF is quantified and is found to be negligible. There is a strong indication of the mass segregation of unevolved single stars and clear signs of a depletion of low-mass stars in NGC 288 with respect to other clusters. The results are in good agreement with the prediction of theoretical models of the dynamical evolution of NGC 288 that take into account the extreme orbital properties of this cluster. Based on observations made with the NASA/ESA Hubble Space Telescope at the Space Telescope Science Institute. STScI is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. These observations are associated with proposal GO-6804.