  It has been suggested that a monitoring program employing the pixel lensing
method to search for microlensing events towards galactic globular clusters may
increase the statistics and discriminate among different halo models.
Stimulated by this proposal, we evaluate an upper limit to the pixel lensing
event rate for such a survey. Four different dark halo models have been
considered changing both the flattening and the slope of the mass density
profile. The lenses mass function has been modelled as a homogenous power - law
for $\mu \in (\mu_l, \mu_u)$ and both the mass limits and the slope of the mass
function have been varied to investigate their effect on the rate. The target
globular clusters have been selected in order to minimize the disk contribution
to the event rate. We find that a pixel lensing survey towards globular
clusters is unable to discriminate among different halo models since the number
of detectable events is too small to allow any reliable statistical analysis.

Astrophysics