is it possible to declare an user group for the remote user in aliases.drushrc.php I have a different user group for apache on my remote server clould i specify a group for drush sync like remote-user user adds the user or in some similar way
?
No; in unix, the group ownership is attached to the user.  Use usermod -a -G to add the desired group permanently to your remote user.  See man usermod for more information.