Diagnosing SQL Server 2012 Using Extended Events - SQL Server 2012 Internals and Troubleshooting - page 375

Ring buffers are stored in a DMV called sys.dm_xe_session_targets , and it's from here you
query their content. This i nal example has created a session called Logins_rb to write its data
to a ring buffer target. To create this yourself, create a new session with the options highlighted in
Figure 13-27 and Figure 13-28.
FIGURE 13-27
FIGURE 13-28