Owin OAuth2 External Authentification

Hello,

I have the following setup: a mvc project for the frontend and a project webapi withOAuth  Authorization Server using OWIN OAuth middleware.

I followed the same scenario presented in this lastprivilege.com article

1. I try and authenticate with an IP(google, twitter etc.),

2. From the IP user is redirected back to the authorization server and gets authenticated

3. then the user is redirected to the frontend with the access token in the link under this format( http://website/#access_token=TOKEN)

What i want to do is authenticate the user after the step 3 is done. Does Owin offer a method to authenticate the user by using the access token or the cookie that is sent

back from the authorization server?

Thank you