How to obtain some fields out of the security log created by SQL Server

Thank you in advance for any input,

I need two get only the user and the date out of the "security log" that shows user's logon/logoff data.
This log is found under Management\SQL Server Logs\Current... then there are several Archives.
The following two selects does not provide me with the same information that the log contains:

select * from sys.server_principals
select * from sys.database_principals