Disable enter submit

I have a form with a textfield inside and I am trying to disable the default behavior when the browser submits the whole form if the user presses Enter while the textfield is selected.

$('#recaptcha_response_field').keydown(function(event) { if (event.keyCode == 13) {
     event.preventDefault();
     event.stopPropagation();
     event.stopImmediatePropagation();
     alert("You Press ENTER key");
     return false;
   } 
});

Currently am getting "You Press ENTER key" and the default behavior isn't overridden.