THE LUMINOSITY FUNCTION AND MASS FUNCTION FOR THE PRAESEPE AND HYADES CLUSTERS

The luminosity function (LF) and present day mass function (PDMF) for main sequence (MS) stars in the Praesepe and Hyades clusters are derived, showing the Wielen dip which occurs at in the LF. This dip is about 2 mag fainter than the case for the Pleiades cluster whose Wielen dip position is consistent with that for the solar neighborhood field stars. The Wielen dips of these clusters are reproduced by using a bimodal initial mass function (IMF).