How to pull two variable using $.get in javascript from a php file

I have a variable that I am retrieving upon a users button press (artist_id), which I am successfully getting. I would like to use this artist_id to find the artist name, which I have in a database. So far I have been unsuccessful exporting the artist name to the javascript as a varaible.

Here is the javascript/jquery:

<script>
$(function() {
  $( "#dialog-modal" ).dialog({autoOpen: false, height: 250, width: 400, modal: true});

  $( "#opener" ).click(function() {
                       $( "#dialog-modal" ).dialog( "open" );

                       $.get('/like_artist.php', {artist_id : $(this).data('artist_id'), stage_name : $stage_name}, function(data) {
                             alert("Data Loaded: " + data.artist_id);


                                                  var text = '';
                                                  var artistId = data.artist_id;
                                                  var stage_Name = data.stage_name;

                                                  text = 'You have liked ' + artistId + stage_Name;
                                                  $('#dialog-modal').text(text);


                             }, "json");

        });

  });
</script>

Here is the php (like_artist.php):

<?php 

session_start();
require_once "database.php";
db_connect();
require_once "auth.php";
$current_user = current_user();
include_once("config.php");




    $artist_id = $_GET['artist_id'];

    $query_two = "SELECT stage_name FROM artists WHERE id='.$artist_id.'";
    $stage_name = mysql_fetch_row(mysql_query($query_two));
    $stage_name = $stage_name[0];

    echo json_encode(array('artist_id' => $artist_id));

   echo json_encode(array('stage_name' => $stage_name));

    $user_id = $current_user['id'];

    $query = "INSERT INTO `user_artists`
    (`artist_id`, `user_id`)
    VALUES
    ('$artist_id', '$user_id')";

    $result = mysql_query($query);



?>

Thank you for the help!