We study the pole structure of the ζ-function associated to the
Hamiltonian H of a quantum mechanical particle living in the half-line
R+, subject to the singular potential gx−2+x2. We show that
H admits nontrivial self-adjoint extensions (SAE) in a given range of values
of the parameter g. The ζ-functions of these operators present poles
which depend on g and, in general, do not coincide with half an integer (they
can even be irrational). The corresponding residues depend on the SAE
considered.Comment: 12 pages, 1 figure, RevTeX. References added. Version to appear in
Jour. Phys. A: Math. Ge