Untwisted Gaiotto equivalence

This is a successive paper of arXiv:1909.11492. We prove an equivalence between the category of finite-dimensional representations of degenerate supergroup $\underset{‾}{GL}(M\mathrm{\mid }N)$ and the category of $(GL_M(O) \ltimes U_{M, N}(F), \chi_{M, N})$-equivariantD-moduleson$Gr_{N}$. We also prove that we can realize the category of finite-dimensional representations of degenerate supergroup $\underset{‾}{GL}(M\mathrm{\mid }N)$ as a category of D-modules on the mirabolic subgroup $Mi{r}_L(F)$ with certain equivariant conditions for any $L$ bigger than $N$ and $M$.