How can I edit this code so that the link comes up in a new window?

code:

function open_window(url) {
var NEW_WIN = null;

NEW_WIN = window.open ("","RecordViewer","toolbar=no,width="+<?php echo $new_window_width ?>+",height="+<?php echo $new_window_height ?>+",directories=no,status=no,scrollbars=yes,resize=no,menubar=no");
NEW_WIN.location.href = url;
}


Thanks,

-JRW