ionic2 - npm install -g ionic@2.0.0-beta.11 cannot install the ionic 2 beta -

please whenever run command npm install -g ionic@2.0.0-beta.11 returns me errors. want install ionic version 2 beta specific requirement. if beta.11 doesn't work. can suggestion me version of ionic 2 beta install. project requires ionic 2 beta.

best regards here error encountred: