wp_query custom post type by taxonomy & standard post by taxonomy

here is the answer:

$args = array(
'post_type'     => array( 'artists', 'post' ),
'post_status'   => 'publish',
'tax_query' => array(
    'relation' => 'OR',
    array(
        'taxonomy' => 'tag_artists',
        'field' => 'slug',
        'terms' => array( 'home' )
    ),
    array(
        'taxonomy' => 'post_tag',
        'field' => 'slug',
        'terms' => array( 'home' )
    )
)
);

$query = new WP_Query( $args );