We prove two results which
show that the categories of smooth and analytic unitary representations of a
Banach–Lie supergroup are well-behaved. The first result states that the restriction
functor corresponding to any homomorphism of Banach–Lie supergroups is
well-defined. The second result shows that the category of analytic representations is
isomorphic to a subcategory of the category of smooth representations. These facts
are needed as a crucial first step to a rigorous treatment of the analytic theory of
unitary representations of Banach–Lie supergroups. They extend the known results
for finite-dimensional Lie supergroups. In the infinite-dimensional case the proofs
require several new ideas. As an application, we give an analytic realization of
the oscillator representation of the restricted orthosymplectic Banach–Lie
supergroup.