angularjs adding field in resource

It seems as if angularjs is adding a field to my model, but I can't figure out why and how to prevent this. Any help would be appreciated!

services.js

factory('Logs', function($resource) {
    return $resource('/api/logs/:ident',{}, {
        get: {method:'GET', isArray: true}
    });
});

controller.js

Logs.get({ ident: $scope.selected_log }, 
        function(data) { // success
            console.log(data) // result is logged - see next code blog
            $scope.log_data = data;
        }, 
        function(data) { // failure
            console.log('failure - could not get the device logs')
        })
}

Result in angular

[
   {  "x":1362045352,
      "y":"100",
      "y0":0 },
   {  "x":1362045536,
      "y":"100",
      "y0":0 }, ...
]

Result using curl on the commandline

[
  {  x: 1362045352,
     y: "100" },
  {  x: 1362045536,
     y: "100" }, ...