D0-branes in SO(32)×SO(32) open type 0 string theory

We construct D0-branes in SO(32)×SO(32) open type 0 string theory using the same method as the one used to construct non-BPS D0-brane in type I string theory. It was conjectured that this theory is S-dual to bosonic string theory compactified on SO(32) lattice, which has SO(32)×SO(32) spinor states as excited states of fundamental string. One of these states seems to correspond to the D0-brane, and by the requirement that other states which do not have corresponding states must be removed, we can determine the way of truncation of the spectrum. This result supports the conjecture.