  For $C^*$-algebras $A$ and $B$, we prove the slice map conjecture for ideals
in the operator space projective tensor product $A \hat\otimes B$. As an
application, a characterization of prime ideals in the Banach $\ast$-algebra
$A\hat\otimes B$ is obtained. Further, we study the primitive ideals, modular
ideals and the maximal modular ideals of $A\hat\otimes B$. It is also shown
that the Banach $\ast$-algebra $A\hat\otimes B$ possesses Wiener property; and
that, for a subhomogenous $C^*$-algebra $A$, $A\hat\otimes B$ is symmetric.
