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We examine the recent results of the MACHO collaboration towards the LargeMagellanic Cloud (Alcock et al. 1996) in terms of a halo brown dwarf or whitedwarf population. The possibility for most of the microlensing events to be dueto brown dwarfs is totally excluded by large-scale kinematic properties. Thewhite dwarf scenario is examined in details in the context of the most recentwhite dwarf cooling theory (Segretain et al. 1994) which includes explicitelythe extra source of energy due to carbon-oxygen differentiation atcrystallization, and the subsequent Debye cooling. We show that theobservational constraints arising from the luminosity function of high-velocitywhite dwarfs in the solar neighborhood and from the recent HST deep fieldcounts are consistent with a white dwarf contribution to the halo missing massas large as 50 %, provided i) an IMF strongly peaked around 1.7 Msol and ii) ahalo age older than 18 Gyr.Comment: 14 pages, 2 Postscript figures, to be published in Astrophysical  Journal Letters, minor revision in tex

Contribution of Brown Dwarfs and White Dwarfs to Recent Microlensing Observations and to the Halo Mass Budget