  Galactic globular cluster (GC) stars exhibit abundance patterns which are not
shared by their field counterparts, In the framework of the widely accepted
"self-enrichment" scenario for GCs, we present a new method to derive the
Initial Mass Function (IMF) of the polluter stars, by using the observed O/Na
abundance distribution. We focus on NGC 2808, a GC for which the largest sample
of O and Na abundance determinations is presently available. We consider two
classes of possible "culprits" : massive Asymptotic Giant Branch (AGB) stars
(4-9 Msun) and winds of massive stars (WMS) in the mass range 10-100 Msun. We
obtain upper limits for the slope of the IMF (assumed to be given by a
power-law) of the stars initially more massive than the present turnoff mass.
We also derive lower limits for the amount of stellar residues. We find that
the polluter IMF had to be much flatter than presently observed IMFs in stellar
clusters, in agreement with the results of two other methods for GC IMF
determination. Additionaly, we find that the present mass of the GC should be
totally dominated by stellar remnants if the polluters were AGB stars, but not
so in the case of WMS. We critically analyse the advantages and shortcomings of
each potential polluter class, and we find the WMS scenario more attractive.
