  We propose the action for a massive $N$-extended superparticle with a pure
(half)integer superspin $Y,~Y = 0, 1/2, 1, 3/2, \ldots$. Regardless of the
superspin value, the configuration space is ${\Bbb R}^{4|4N} \times S^2$, where
$S^2$ corresponds to spinning degrees of freedom. Being explicitly
super-Poincar\'e invariant, the model possesses two gauge symmetries implying
strong conservation of the squared momentum and superspin. Hamilton constrained
dynamics is developed and canonical quantization is studied. For $N$ = 1 we
show that the physical super wave-functions are to be on-shell massive chiral
superfields. Central-charges generalizations of the model are given.

High Energy Physics - Theory