I am trying to understand a family of types in the set $S(A)$, which turns out to be a $G_{\delta}$ set. Hence the following questions came up:

1. What is know about the subspace topology induced over a $G_{\delta}$ set?

2. Is there any possible topology that one could induce over $S(A)$ that makes and $F_{\sigma}$ set closed? 

3. Which properties of convergence could be stated among sequences in a $G_{\delta}$ set?

Any comment, help or reference will be highly appreciated.